KR101358806B1 - Method and apparatus for enabling a mobile terminal to change between heterogenous wireless networks while receiving data using minimum resources of a wireless network - Google Patents

Abstract

The present invention receives or transmits data in preparation for connection switching. The wireless communication terminal according to the present invention, if the set restriction information designates a limit value, receives the media data from the external server while buffering the media data below the limit value through the connected wireless communication network, and decodes the buffered media data. A receiving unit for providing to a processing unit for processing and restriction information specified for the type of the connected wireless communication network from the restriction information specified for each of a plurality of wireless communication networks, and configured to be set in the receiving unit; And a control unit configured to change the limit value to a larger emergency value and set the receiving unit before the connection of the communication terminal is switched. The restriction information specifies different buffering rules for at least two of the plurality of wireless communication networks.

Description

Method and apparatus for enabling a mobile terminal to change between heterogenous wireless networks while receiving data using minimum resources of a wireless network}

The present invention provides a method for selectively transferring a plurality of heterogeneous networks, in particular, a plurality of heterogeneous networks having different characteristics of a service area or quality of service between a wireless communication terminal and a server so that data of a server is transmitted to the terminal. And an apparatus for the method.

With the development of wireless communication network, users can receive various information and contents that they need regardless of the place using not only mobile phones but also smart phones and tablet computers.

Users access and use high-speed wireless data networks, such as Wi-Fi wireless networks, that can support them in real time in case of large amounts of information or content, and, for example, cellular (cellular) ) Tends to use data services of mobile communication networks. This seems to be due to a communication environment in which high-speed wireless data networks are mainly serviced only in limited areas and provide a cost-effective communication infrastructure for users.

However, as mentioned earlier, high-speed wireless data networks are only available in limited areas that are geographically dispersed, which may be a complaint for users with high mobility or low accessibility. There is no choice but to. To resolve these complaints, service providers are required to reduce the barriers to the use of data services through mobile telecommunication networks that can service virtually all areas except radio shade areas, or to use unlimited data services at fixed rates. Introduced.

According to the service provider's tariff policy, the utilization rate of the data service through the mobile communication network of wireless communication terminals increases, and the provision of high-quality video or information that requires high speed through the mobile communication network increases. As a result, the data load on the public mobile telephone network is significantly increased, and this increase in load dramatically reduces the channel or bandwidth for general purpose communication, such as voice calls. It is also raising.

In order to solve this problem, telecommunication operators are in a hurry to commercialize wireless communication networks for high-speed data services such as 4G networks (also called “LTE networks”). This is limited at this time and a considerable amount of time is required for widespread service. In addition, the terminals that can use the LTE network is not widely spread, and users are hesitant to subscribe to the service using the corresponding network due to the cost burden. For this reason, severe data loads on existing mobile phone networks may continue for a considerable time.

Therefore, in addition to a tariff or technical solution for guiding data services using public mobile telecommunication networks to other wireless telecommunication networks, there is a need for a method of reducing the load itself according to a specific data service applied to the mobile telecommunication network. .

The present invention, while playing the content data using a data service through a specific wireless communication network, while maintaining a minimum amount of buffering, so that the video currently played when switching to another wireless communication network can be played seamlessly It is to provide a method and apparatus.

It is still another object of the present invention to provide a method and an apparatus for continuously connecting content currently played when switching to another wireless communication network even when there is a limitation of currently used communication network resources.

It is to be understood that the object of the present invention is not limited to the explicitly stated objects, but, of course, it is an object of the present invention to achieve the effect which can be derived from the following specific and exemplary description of the present invention.

According to an aspect of the present invention, a wireless communication terminal capable of accessing a plurality of wireless communication networks, if the set restriction information designates a limit value, buffers media data below the limit value through the connected wireless communication network. Receiving unit for receiving from an external server and providing to the processing unit for decoding the buffered media data, and restriction information specified for the type of the connected wireless communication network, respectively, in the restriction information specified for the plurality of wireless communication networks. It is configured to select and set to the receiving unit, and further comprising a control unit configured to change the limit value to a larger emergency value and set the receiving unit before the connection of the wireless communication terminal is switched. The restriction information specifies different buffering rules for at least two of the plurality of wireless communication networks.

In one embodiment according to the present invention, a limit value included in the restriction information set in the reception unit for a wireless communication network having a wide-area service area is a wireless communication network that provides data service for a limited area by a distributed service area. It is specified as a value smaller than the above limit set for.

In one embodiment according to the present invention, the control unit is further configured to change and reset the limit value set in the receiving unit according to the communication state of the connected wireless communication network. In the present embodiment, the control unit changes the limit value to a smaller value when the load of the connected wireless communication network is greater than or equal to a predetermined reference value, or the limit value is larger when the variability of the connected wireless communication network is greater than or equal to the reference value. It may be configured to reset to the receiver by changing to a value.

In one embodiment according to the present invention, the control unit, if the amount of data using the data service of the specific wireless communication network of the wireless communication terminal of the plurality of wireless communication network is higher than the reference amount, the limit value specified to set for the connected wireless communication network And configured to set the receiver to a lower limit value.

In one embodiment according to the present invention, the control unit, if the server for transmitting the media data corresponds to a predetermined server, the receiving unit as a limit value different from the limit specified to set for the connected wireless communication network Is further configured to set on.

In one embodiment according to the present invention, the control unit is configured to change the limit value to the emergency value when the state of the wireless communication terminal corresponds to a connection switching precondition. Here, the connection switching precondition is a reception of a command for requesting to switch to a specific wireless communication network among the plurality of wireless communication networks from outside, or when a new wireless communication network other than the connected wireless communication network becomes accessible. Alternatively, the wireless communication terminal may be in a mobility state.

In one embodiment according to the present invention, the control unit is further configured to attempt to switch the connection of the wireless communication terminal when the buffering value for the media data of the receiving unit is greater than or equal to the switching value. Herein, the conversion value is greater than at least one of the limits specified in the different rules, and is less than or equal to the incompatibility value. In the present embodiment, the control unit, before attempting to switch the connection, provides information indicating that the connection can be switched on the screen of the wireless communication terminal, and then switch the connection through the user interface of the wireless communication terminal. Attempt to switch the connection when there is a request of.

In another embodiment according to the present invention, the control unit is further configured to notify the execution object executed in the wireless communication terminal when the buffering value for the media data of the receiving unit is greater than or equal to the conversion value. .

In the above embodiments, the switching value may be designated as a different value depending on the type of wireless communication network to be newly connected or the type of connection point to be newly connected by the switching of the connection.

In one embodiment according to the present invention, if the limiting value is changed and set to the emergency value, the media from the operating system of the wireless communication terminal until the buffering value of the media data corresponds to the emergency value. It is configured to repeat the reading of the socket by increasing the read speed for the socket through which data is delivered. Alternatively, when the limiting value is changed and set to the non-commercial value, the receiving unit changes the received media data into media data having at least partly the same content but requiring a lower required speed than the received media data. An operation may be performed. This operation is performed when the transmission speed of the media data in the wireless communication area is insufficient to increase the buffering value of the media data to the emergency value.

In one embodiment according to the present invention, the control unit is further configured to reset the restriction information specified for the type of the wireless communication network newly connected to the receiving unit when the connection is switched. In the present embodiment, when there is a change in the connection, the receiving unit requests a request by a communication protocol requesting data from a point subsequent to the media data received from the previously connected wireless communication network through the newly connected wireless communication network. By transmitting to an external server, the media data is further configured to subsequently receive while buffering according to the buffering rules specified by the reset restriction information. Here, the switching of the connection may be a switching between the plurality of wireless communication networks or reconnection in the same wireless communication network.

In one embodiment according to the present invention, the emergency value may be set to a value equal to or greater than a value corresponding to the maximum bufferable amount of the media data of the receiver.

In one embodiment according to the present invention, the different buffering rules may be designations of limit values of different sizes limiting buffering by the receiver.

In another embodiment according to the present invention, the different buffering rules may be to designate a limit limiting buffering by the receiver and a non-limiting buffering by the receiver, respectively.

In one embodiment according to the present invention, if the connected wireless communication network is a predetermined wireless communication network, the control unit does not change and set the limit value to the emergency value even before the connection of the wireless communication terminal is switched. It is configured not to.

According to another aspect of the present invention, a method for receiving media data in preparation for a connection change includes identifying a type of a wireless communication network connected for data communication with a remote server and specifying a buffering rule for the type. A first step of setting restriction information, a second step of receiving media data provided from the remote server while buffering it below the limit value specified as the buffering rule, and in a pre-state state before the wireless communication terminal performs connection switching. Checking whether there is a state, and if the state is present, changing the limit value to a larger non-commercial value and setting the limit value to 4 non-critical values; It is composed. In the method, the restriction information specifies different buffering rules for at least two of the plurality of wireless communication networks including the wireless communication network.

In one embodiment according to the present invention, the method may include: a communication state of the connected wireless communication network, an amount of data using a data service of a specific wireless communication network of the wireless communication terminal, or whether the remote server belongs to a predetermined server; The method further includes changing and setting the limit value specified in the limit information.

According to another aspect of the present invention, there is provided a program supply device including: communication means capable of transmitting / receiving data to / from an external device via communication; storage means for storing an application executed in the wireless communication terminal, . When the application is executed in the wireless communication terminal, the application checks the type of the connected wireless communication network and selects the restriction information specified for the identified type from the restriction information specified for a plurality of wireless communication networks. A function for receiving a function from the external server while buffering the media data below the limit through a connected wireless communication network, and if the selected restriction information specifies a limit value, the processing unit for decoding the buffered media data. And a program structure for performing a function for providing and for changing and setting the limit value to a larger emergency value before the connection of the wireless communication terminal is switched. The restriction information used by the application specifies different buffering rules for at least two of the plurality of wireless communication networks.

In accordance with another aspect of the present invention, a method for transmitting media data in preparation for a connection change of a terminal includes: providing the wireless communication terminal by a first limit value specified for the type of first wireless communication network to which the wireless communication terminal is connected; In step 1, after the transmission of the media data to the wireless communication terminal as the first data rate to increase the data buffering at, the transmission speed of the media data is reduced to the second data rate; When the information indicating that the device is in the pre-state state is received, the media data is changed to a third data rate faster than the first data rate so that data buffering at the wireless communication terminal increases to an emergency value larger than the first limit value. Transmitting the media through the second wireless communication network; If the request for transmission of data, comprises a third step of adjusting the transmission rate of the media data to the first data buffered in the second by a second limit value specified for the type of wireless radio communication terminal increases. In the present method, when the first wireless communication network and the second wireless communication network are different types, the first limit value and the second limit value have different sizes.

In one embodiment according to the invention, the second data rate is a rate corresponding to the decoding rate required when the media data is played.

In one embodiment according to the present invention, the method comprises a value different from the second data rate based on the communication status of the first wireless communication network or the amount of data using a data service of a specific wireless communication network of the wireless communication terminal. And transmitting the media data for a predetermined time by changing the data rate, and changing the transfer rate back to the second data rate. Information on the data amount using the communication state or data service is received from the wireless communication terminal or another server.

In one embodiment according to the present invention, the information informing that the wireless communication terminal is in a pre-state before performing connection switching is received from the wireless communication terminal or another server. Herein, the information indicating that the mobile station is in a pre-state state may include information indicating that the wireless communication terminal should be switched to a specific communication network, information indicating that a new wireless communication network other than the connected first wireless communication network is accessible, or the wireless communication. Information indicating that the communication terminal is in a mobility state.

In one embodiment according to the invention, the method further comprises the step of measuring the supported speed on the transmission path to the wireless communication terminal while transmitting the media data at the second data rate. In the second step, if the measured support rate is less than the third data rate, the media data having at least partially the same content as the transmitted media data but having a required required speed is lower than that of the transmitted media data. The method further includes the step of transmitting to change. At this time, the changed media data may be transmitted at a rate higher than the second data rate within the measured support rate.

In accordance with another aspect of the present invention, a method of transmitting media data in preparation for a connection change of a terminal includes: a first step of receiving a content request from the wireless communication terminal, and a first connection to the wireless communication terminal; Determining a first transmission rate for the requested content according to a type of a wireless communication network; transmitting the media data of the requested content to the wireless communication terminal at the determined first transmission rate; If the information indicating that the wireless communication terminal is in the pre-state before performing the connection switching is received, it comprises a four step of transmitting the data of the content at a conversion contrast rate faster than the determined first transmission speed. In the second step, when the wireless communication terminal is connected to a second wireless communication network of a type different from that of the first wireless communication network, a second transmission speed having a value different from the first transmission speed for the content is provided. Further comprising the step of determining.

In accordance with another aspect of the present invention, an apparatus for providing media data while preparing for connection switching of a terminal is configured to be connected to a communication network to transmit media data to the wireless communication terminal, and also to the wireless communication terminal or another device. And a communication processing unit configured to receive information about a state of the wireless communication terminal through the communication network, and to allow media data of content selected by a request from the wireless communication terminal to be transmitted through the communication processing unit. And an information processing unit configured to control the communication processing unit such that a transmission speed is adaptively adjusted according to the information regarding the state.

If the information processing unit of the device indicates the type of wireless communication network to which the wireless communication terminal is connected, the information processing unit is configured to perform the information on the wireless communication terminal by the first limit value specified for the type of wireless communication network. To increase the data buffering so that the transmission rate of the communication processing unit becomes the first data rate, and then lower the transmission rate to the second data rate; A third data rate in which the transmission rate of the communication processing unit is faster than the first data rate so that data buffering in the wireless communication terminal increases to an emergency value greater than the first limit value if informing the pre-state before performing the switching. It is configured to be.

If the information processing unit of the device indicates the type of wireless communication network to which the wireless communication terminal is connected, the information processing unit causes the communication processing unit to determine the first transmission rate determined for the type of the wireless communication network. And transmitting the media data, and if the information about the state informs the pre-state before the wireless communication terminal performs the connection switching, causing the communication processing unit to switch the conversion speed faster than the first transmission speed. It may have a configuration to transmit the media data as a speed. Here, in the case of a wireless communication network of a different type from the wireless communication network to which the wireless communication terminal is connected, the second transmission rate determined by the information processing unit to transmit the media data has a value different from the first transmission rate. Have

In the above-described method and apparatus, the first transmission rate and the second transmission rate are determined based on a data rate required when playing the content, all of which are determined to be faster than the data rate. The conversion rate is faster than at least one of the first transmission rate and the second transmission rate.

At least one embodiment of the present invention described above, or described in detail with reference to the accompanying drawings, allows a wireless communication terminal to display a buffering value (a buffering amount or play time by the amount) of media data to be played. When necessary, for example, when the supply of data for play is likely to be restricted for a certain period of time, it is necessary to reserve more as appropriate, so that the buffering amount through the wireless network can be kept to a minimum in normal operation conditions. To help.

Therefore, according to the present invention, the wireless communication terminal does not need excessive data buffering for safe media play even in a situation in which connection switching may occur arbitrarily, for example, when network switching is possible or mobile. This reduction in the amount of buffering can reduce the load on the wireless communication network to some extent. Given that most of the use of information using wireless networks involves the transmission of video media, such load reduction at each wireless terminal can have a significant effect on the overall load reduction of the wireless network.

1A is a logical view of a programmatic view of related components of a wireless communication terminal in which an embodiment of a method for switching between heterogeneous networks while receiving data using minimum resources of a wireless communication network according to an embodiment of the present invention is implemented. Are examples of configurations and externally connected configurations,
FIG. 1B illustrates a configuration of a wireless communication terminal in which a method of switching between heterogeneous networks while receiving data using minimum resources of a wireless communication network is implemented according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating configurations of a media player in a wireless communication terminal, in which configurations of a media player are received and decoded using a minimum amount of resources of a wireless communication network while ensuring sufficient data buffering before switching between heterogeneous networks, according to an embodiment of the present invention. Shown with the components,
3A and 3B are examples of a flowchart according to a method of controlling data reception speed so as to receive data using a minimum of resources of a wireless communication network and to ensure sufficient data buffering before switching between heterogeneous networks according to an embodiment of the present invention. ego,
4A through 4C schematically illustrate respective correlations that may occur upon data reception with respect to a buffering limit set in accordance with an embodiment of the present invention and a data buffering state,
5 is a diagram illustrating a process of reading data through a socket and filling a buffer up to the limit for data throttling according to a set buffering limit according to an embodiment of the present invention.
FIG. 6 schematically illustrates a process of increasing the buffering limit to sufficiently buffer data when the terminal corresponds to a connection switching precondition, according to an embodiment of the present invention.
FIG. 7A is an example of media index information created for the case of providing each of media components of various quality and / or attributes in live for a single content; FIG.
7B is an example of list file information in which a list of files, etc., to be sequentially requested for access to the live video media is described.
8 exemplarily illustrates a process of changing and receiving a video or audio component that requires a lower required speed from received live video content;
9 is an example of configurations of an entire system to which an embodiment of a method for allowing a terminal to switch between heterogeneous networks while transmitting data using a minimum amount of resources of a wireless communication network according to another embodiment of the present invention is applied;
FIG. 10 illustrates an example in which a data transmission rate of a server is adjusted so that data buffering in a wireless communication terminal is appropriately adjusted according to a necessary situation, according to an embodiment of the present invention.
11 is a diagram schematically showing an example in which data buffering is reduced in a wireless communication terminal by adjusting a transmission speed according to an embodiment of the present invention.
12 is a diagram illustrating a process of a server grasping a transmission speed to a terminal at the time of transmitting content data, in order to know a possible width of a subsequent transmission speed adjustment according to an embodiment of the present invention.
FIG. 13 is a diagram for explaining a process of increasing a buffering value in a terminal by changing the quality of the content without adjusting the transmission speed of the content according to an embodiment of the present invention.
14 illustrates an example in which a data transmission rate of a server is adjusted so that data buffering in a wireless communication terminal is properly maintained according to another embodiment of the present invention.
FIG. 15 illustrates an example of a configuration of a content server that allows a terminal to switch between heterogeneous networks while transmitting data using a minimum amount of resources of a wireless communication network according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1A is a logical view of a programmatic view of related components of a wireless communication terminal in which an embodiment of a method for switching between heterogeneous networks while receiving data using minimum resources of a wireless communication network according to an embodiment of the present invention is implemented. It illustrates the configuration and externally connected configuration.

The logical configuration of the programmatic view of the wireless communication terminal 100 illustrated in the figure is the driving of hardware resources (illustrated in FIG. 1B) of the wireless communication terminal 100, appropriate signals and / or information with the corresponding resources. A media player 110 having a normal operating system (Android, IOS, Window, etc.) or an operating system 100a specialized for the present invention for performing the exchange, and which is executed under the operating system 100a, is also provided. Include. Of course, various applications other than these may be implemented, but are unnecessary in describing the principles and concepts of the present invention, and thus, examples of the conventional applications (hereinafter, abbreviated as "applications") will be omitted.

The media player 110 illustrated in the drawing is a process or application implemented in the wireless communication terminal 100, and the code executed based on the operating system 100a as illustrated in FIG. 1A. It may be provided in the form of software having a program structure consisting of. When provided in the form of software, the media player having the mass storage means and recorded in the mass storage means through a normal on-line purchase process or the like from a specific server connected to the communication network through the provided communication means. 110 may be executed after being downloaded and installed in the wireless communication terminal 100. In some cases, at least some of the functions of the media player 110 described in detail below are in the form of middleware or a platform on which applications are based, or in the operating system 100a. It may be implemented in the wireless communication terminal 100 in some form. In addition, since the media player 110 includes a hardware configuration, the hardware may perform some of the functions described in detail below. Accordingly, the scope of the present invention is not limited to the media player 110 whose configuration and operation method are described in detail in various embodiments according to the present invention.

In one embodiment according to the present invention, the media player 110 is provided with a media processing unit 111 for processing a received data object, for example, content data of a media attribute, and the operating system 100a. A data transmission / reception unit 112 for generating a communication socket through an application program interface (API) and transmitting / receiving data exchanged with the media processing unit 111 to the outside through the generated communication socket, and transmitting and receiving the data. And a reception control unit 113 for controlling the data reception speed of the unit 112 as a sub process, and data for data transfer or exchange between the media processing unit 111 and the data transmission / reception unit 112. The channel includes a reception buffer 113a and a transmission buffer 113b. In another embodiment according to the present invention, a transmit buffer may not be implemented. In the present embodiment, the media processing unit 111 provides the data transmission / reception unit 112 to the data transmission / reception unit 112 via mediators or the like to be transmitted to an external server according to a user's request. 112) composes and sends a request according to the communication protocol, for example, an HTTP request. In another embodiment of the present invention, a UI processing unit for processing a user request may be implemented as a separate process from the media processing unit 111. [ In the present embodiment, the UI processing unit provides data or request information to be transmitted to an external server in response to a user's request to the data transmission / reception unit 112 through mediators and the like.

In one embodiment according to the present invention, instead of the reception buffer 113a, a memory space shared between the media processing unit 111 and the data transmission / reception unit 112 may be allocated and used as a data channel. In this case, the media data may be transferred to each other in such a manner that the data is recorded at an arbitrary position in the shared memory space and the recorded position is notified.

In addition, the data transmission / reception unit 112 checks the current wireless communication network accessible from the plurality of available heterogeneous networks 11a, 11b, ... through the operating system 100a, and receives the allocation from the wireless communication network. By using a connection IP address or requesting assignment of a connection IP address from another wireless communication network, data is transmitted and received with an external server (for example, the content server 12 in the drawing) through a communication network required according to conditions. In addition, even in the case of the switching of the wireless communication network, the data buffered in the receiving buffer 113a is continuously required after the network switching in order to ensure the continuity of the currently played content, for example, seamless smooth connection. It also performs the request of communication protocol, for example, generating and sending HTTP Request. This operation of the data transceiver 112 will be described in detail later. In addition, the media processing unit 111 may generate a request according to a necessary communication protocol in response to a request from a user and transmit the request to the external server by transmitting the request to the data transmission / reception unit 112 through the transmission buffer 113b.

In one embodiment according to the present invention, the data transmission and reception unit 112, the media processing unit 111, and the reception control unit 113 are implemented together as a single process performed on the basis of the operating system 100a. May be In this case, information or data exchange between each other can be made through global variables, internal variables or a factor and / or return value of a local function. Accordingly, the concept, the subject matter, and the desired effect of the present invention may presuppose or require a process in which the data transmitting / receiving unit 112, the media processing unit 111, and the receiving control unit 113 are separated and executed separately. The functions described below can be naturally achieved even in the form of a single process.

Meanwhile, the wireless communication terminal 100 having the logical configuration illustrated in FIG. 1A includes a hardware component as illustrated in FIG. 1B as a whole, and includes a public mobile telephone network or a high-speed wireless data network. It may be any one of a smart phone, a tablet computer, a laptop having a mobile phone function, and the like, which can selectively access a wireless communication network. Looking specifically at the configuration illustrated in the drawings, the public mobile phone network, for example, 2G, 3G or 4G cellular mobile phone network (hereinafter referred to as "cellular network") of the designated method According to the cellular modem 1a (a component including an RF signal processing module) for transmitting and receiving a signal to and from a corresponding communication network, and encoding or encoding data according to a communication protocol adopted by the cellular network. In accordance with a specified method of a cellular codec 1b for decoding the decoded data and a high-speed wireless data network, for example, a Wi-Fi wireless LAN network (hereinafter referred to as a "Wi-Fi network"). Encodes or encodes data according to a Wi-Fi modem 2a (a component including an RF signal processing module) that modulates or demodulates a signal with a corresponding communication network, and a communication protocol adopted by the Wi-Fi network. Wi-Fi codec (2b) for decoding the data frame, a display panel (5) for displaying images, characters, etc., and the display panel (5) so that arbitrary data is visually displayed on the display panel (5) A display driver 4 for driving, a decoder 110a for decoding input encoded video and audio data and outputting the video and audio signals, a touch sensor 6a attached to the front of the display panel 5, And a keypad 6b equipped with a key and / or a button, and detecting user input and / or selection on the touch sensor 6a and the keypad 6b and outputting corresponding input information. To transmit or receive data from or control data appropriately among the above components so that an operation according to the input information from the input control unit 6 and the input information from the input control unit 6 is performed. A main controller 10 for controlling the display driver 4 for displaying a UI screen for selecting a result or a desired operation of the user, and a memory for providing data storage space necessary for the operation of the main controller 10; Part 7 is included.

In addition, the main controller 10 allows the operating system 100a to perform the intended function by executing the given command codes, and also executes the command codes of the media player 110 to execute the command codes described in detail below. The operations of the media player 110 are performed. In particular, the media processing unit 111 of the media player 110 may transmit the encoded data or audio data blocks through an appropriate application program interface (API) provided by the operating system 100a, A decoding operation that the decoder 110a performs in hardware may be used.

The configuration of the wireless communication terminal 100 illustrated in FIG. 1B is just one example for specifically and illustratively explaining an embodiment for helping understanding the concept and the subject of the present invention, and according to the present invention. Terminals implementing the subject matter may further include components of various functions not shown in FIG. 1B or may exclude the illustrated components, and hardware components may be implemented in software.

A process of data reception control in preparation for the reception of content data and the switching of the communication network, and the communication network, which are made by the wireless communication terminal 100 whose logical configuration is illustrated around the media player 110 in FIG. 1A. Is done as follows:

First, a user may provide an appropriate user UI provided by the main controller 10 through an input / output unit (the display panel 5, the touch sensor 6a, the keypad 6b, etc.) provided in the wireless communication terminal 100. When a browser is started through a user interface and a particular server, for example, a single content provided by the illustrated content server 12 is selected and requested through the browser, a communication protocol according to the request is requested. A request, for example, an HTTP Request for a URL such as “http://vod.airplug.com/video/movieABC.mp4”, is forwarded to the operating system 100a, and the operating system 100a stores the current data. Hardware resources for use of a wireless communication network (i.e., an access IP address is assigned) for service (if the cellular network 11a is connected, the cellular codec 1b / cellular modem 1a, Wi-Fi network ( 11b) is connected, the Wi-Fi codec (2b) / Wi-Fi Through (2a)), it transmits the request by the communication protocol transmitted. Accordingly, when a response from the content server 12, for example, data related to the selected content is received through the requested communication network, it is provided to the browser.

The response received by the browser includes, in addition to the content data transmitted by the content server 12, file description information on content provided in the response, for example, MIME (Multipurpose Internet Mail Extensions) type, content data. Contains information about the overall size of the. Thus, the browser launches the media player 110 which is an application connected to the mime type of the received response. The media player 110 may be connected by an extension of a file other than the mime type. When the browser activates the media player 110, a request generated by the URL or a communication protocol written accordingly, for example, an HTTP request or an RTSP / RTP request, is sent to the started media player 110. Pass as a call argument.

Up to now, the process of starting the media player 110 has been described on the assumption that the process is performed through a browser that is commonly used. However, the media player 110 may be started by various applications besides the illustrated browser. That is, when an access information, for example, a URL, for a specific content is selected in an application, the application may start the media player 110 by performing the same process as the above-described browser.

Alternatively, after the media player 110 is started without a request by a mediated URL or a communication protocol, the media player 110 may be directly received or selected through a user UI. The data transmission / reception unit 112 is notified of the URL directly received or selected, or a request according to the communication protocol.

When the media player 110 is activated, the reception control unit 113 allocates the reception buffer 113a and the transmission buffer 113b to the memory 7 and allocates each of the allocated buffers 113a and 113b. The information for accessing the data is shared between the media processing unit 111 and the data transmission / reception unit 112. Then, the data transmission / reception unit 112 is notified to the data transmission / reception unit 112 previously transmitted at the start-up, and the data transmission / reception unit 112, as illustrated in FIG. A request is made to create a new communication socket 22 while providing a request to the operating system 100a. The request at this time may be for a wireless communication network to which the operating system 100a is currently connected for data service, or may designate a specific wireless communication network. In order to designate a communication network, the data transmission / reception unit 112 refers to the network connection information returned by inquiring of the operating system 100a. The network access information includes a connection IP address and a connection type (for example, 3G mobile telephone network, Wi-Fi wireless LAN network, etc.) when connected to a wireless communication network. You can request the creation of a communication socket either by specifying a connection type or by specifying the associated IP address.

The operating system 100a is based on the information (for example, protocol information described in the request, the name or IP address of a host field, etc.) described in the request according to the received communication protocol, and the content as the destination of the information. A TCP connection is established with the server 12. When the TCP connection is successfully established, the operating system 100a returns the identifier of the generated communication socket 22 to the data transceiver 112 in response to the communication socket creation request.

When the generated identifier of the communication socket 22 is returned, the data transmission / reception unit 112 identifies the type (eg, 3G mobile telephone communication network, Wi-Fi wireless LAN network, etc.) of the communication network used by the communication socket. After notifying the reception control unit 113, through the communication socket 22 specified by the returned identifier, the request of the communication protocol notified before is sent back to the content server 12, and the browser Receives the response received through the newly created communication socket 22. At this time, in order to use the request by the communication protocol to be transmitted later, for example, a request document created according to the HTTP syntax for a URL such as “http://vod.airplug.com/video/movieABC.mp4”. The request is stored separately in association with the communication socket 22 that transmitted the request. In one embodiment according to the present invention, the request document may also be provided for the reception control unit 113 to refer to the data reception control operation described below. Meanwhile, the browser transmits a request based on a communication protocol for stopping transmission of the response data through the communication socket 21 ₁ at which the response data is being received, or at the same time as the start request of the media player 110. It is also possible to close the socket 21 ₁ .

The data transmission / reception unit 112 reads the response data received through the newly created communication socket 22 and interprets the data based on a communication protocol, for example, HTTP or RTSP / RTP, and then streams the response. ) Data of the media file is moved to the receiving buffer 113a in order. The metadata for the content data is extracted from the response and stored separately for later use and transmitted to the reception controller 113 at the same time. The meta data includes media information extracted from the head of the media file data, in addition to the above-described file description information provided according to a protocol format for media file transmission. This media information includes content reproduction time information.

The media processing unit 111 draws out the media data accumulated in the reception buffer 113a in order in the above manner, determines the decoding method based on the encoding information of the data recorded in the header of the data, and then determines the decoding method. Decode the media data partially or completely according to the decoding scheme. In case of partial decoding, the decoder 110a also sets the determined decoding method. The partial decoding may be extraction of media packets, for example, block unit, picture unit, or Group of Pictures (GoP) unit. In the case of the partial decoding as described above, the decoded media packets are applied to the decoder 110a to request decoding so that video and audio signals thereof are output. The video data completely decoded by the media processing unit 111 is applied to the display driver 4 through the operating system 100a to be output as a video signal.

On the other hand, the reception control unit 113 maintains only the load applied to the currently used communication network according to the use of the data service as necessary, and there is a possibility that a failure or inconvenience in using the user's data service may be caused. Only to increase the resource usage of the communication network, the data reception control method illustrated in Figures 3a and 3b is performed. In order to perform this control method, the reception control unit 113 sets restriction information in the data transmission / reception unit 112 (S301). The restriction information is information for specifying a rule for data buffering, and the rule includes whether to limit buffering or a reference value for limiting buffering, that is, a buffering limit value. When setting the restriction information, the reception control unit 113 allows different buffering rules, that is, buffering limits of different sizes, to be set according to the type of the wireless communication network used by the communication socket 22. For example, the limit for the cellular network 11a is set to, for example, 1/2 or 1/3 of the limit for the Wi-Fi network 11b. Of course, if the number of available wireless networks is three or more, the same size limit may be specified for different networks, but in embodiments according to the invention, different sizes of at least two different networks may be employed. The limit value is specified. When the value of the buffering limit decreases, the amount of data buffering also decreases. The reason for making the limit for the cellular network 11a smaller than that for the Wi-Fi network 11b is that the cellular network 11a Compared to the Wi-Fi network 11b, the service characteristics are relatively less volatile and have a wider service area. Therefore, despite the small amount of buffering, the buffer underrun (in this case, there is no data to be decoded, This is because the probability of occurrence) is quite low.

In one embodiment according to the present invention, in the case of a connection of a specific wireless communication network, for example, the Wi-Fi network 11b, the data transmission / reception unit provides restriction information indicating buffering non-limiting as a buffering rule. It may be set to 112. When the restriction information of such a rule is set, in the state connected to the Wi-Fi network 11b, the deceleration operation described later is not performed. The same applies when the restriction information is a rule for specifying a buffering limit value having a value greater than or equal to the storage capacity of the reception buffer 113a.

In one embodiment according to the present invention, when determining a limit value according to the type of wireless communication network to be used, the request document of the content data transmitted from the data transmission and reception unit 112 is previously confirmed, and the request is provided with specific information previously designated. If the server is applicable, the limit value defined for the type of wireless communication network may be adjusted, that is, reduced or increased to be changed to a value specified for the specific information providing server, and then set in the data transceiver 112. Of course, after setting the limit value for the wireless communication network type, it may be reset by adjusting the limit according to the specific server.

On the other hand, although the buffering limit value by the restriction information to be set by the reception control unit 113 is basically determined as the time length, when setting the determined value to the data transmission / reception unit 112, it is not set as the determined time length but as the data amount. Can also be set. In the case of setting the data amount, the total size and the playback time of the corresponding content are grasped from the meta data transmitted from the data transmitting / receiving unit 112 to set the data amount corresponding to the time length of the limit value to be set. . That is, when the time length of the determined limit value is ThRef_T, if the file size of the content is file_D and the playback time is P_TIME, the data amount ThRef_S of the limit value to be set is determined by the following equation [1].

ThRef_S = ThRef_T * (file_D / P_TIME) expression [1]

Here, file_D / P_TIME is a required speed required for playing the content, that is, a decoding speed.

Equation [1] is equally applied when the data transceiver 112 determines the amount of data corresponding to the time length, when the limit value is set in the data transceiver 112 as a time length. Of course, in order to perform the deceleration operation according to the limit described below without converting the time length to the data amount, the corresponding time length Arb_DataT is obtained by using the arbitrary data amount Arb_DataS using the following equation [2]. It can also be used to compare with the set limit in terms of.

Arb_DataT = Arb_DataS * (P_TIME / file_D) Expression [2]

Therefore, in the embodiments according to the present invention, the physical capacity of both comparing or corresponding to each other with respect to the storage capacity of the reception buffer 113a, the limit value, the data amount, and the conversion value described below. When units differ from each other, either of them is converted into a physical quantity of the same unit by the above formula [1] or [2] and compared.

When the buffering limit value is set, the data transmitting / receiving unit 112 performs an operation of reducing the media data accumulated in the receiving buffer 113a through the communication socket 22 so as not to exceed the limit value. (S302). In one embodiment according to the present invention, the deceleration operation may be performed only for a specific wireless communication network. In the present embodiment, if the generated communication socket 22 is not for the specific wireless communication network, the reception control unit 113 instructs deactivation, that is, release of the deceleration operation, instead of setting the buffering limit value. The restriction information is notified to the data transmitting / receiving unit 112, in which case, the reception control operation illustrated in Figs. 3A and 3B is not performed.

In one embodiment according to the present invention, after setting the limit value for the deceleration operation in the data transmission and reception unit 112, the limit value determined and set according to the type of the use network is set to the current communication state or data use state ( In the following, it is abbreviated as " communication status / use status " For example, if the communication state of the service area of the currently connected wireless communication network is highly volatile, the reception control unit 113 changes the buffering limit value to a larger value and resets the data transmission / reception unit 112. . For example, in the case where the wireless communication network currently used is the Wi-Fi network 11b, if the change in the signal strength of the access point (AP) periodically checked according to the method described below is greater than the reference width, The buffering limit value is increased according to the average value of the change width and reset to the data transceiver 112. Further, the buffering limit value may be adjusted and set according to the load degree in the service area of the currently connected wireless communication network or according to the amount of data used by the wireless communication terminal 100. Information on the load in the service area and information on the data service usage amount of the terminal may be received and used from an external specific server. The access information for accessing these servers is predetermined by the reception controller 113 or set by the user through an input window provided by the media player 110 on the display panel 5 through an appropriate UI. The reception control unit 113 shares specific address information of the server. Of course, in order to obtain the above information, the reception control unit 113 may provide information for identifying a service area (for example, an ID of a service cell) or information for identifying itself (a subscriber's phone number). It is provided to a specific server.

In addition, according to an embodiment of the present invention, if the load (traffic amount) on the current service area identified as described above is greater than or equal to a predetermined reference value, or the amount of data using a data service is larger than a predetermined reference amount, The set limit is adjusted to be smaller to reset the data transmission / reception unit 112. Alternatively, when setting the initial limit value for the type of wireless communication network, it may be adjusted and set to a limit of a size smaller than the limit for the corresponding wireless communication network in consideration of the data service usage amount. As such, adjusting the buffering limit to a smaller value increases the likelihood that exhaustion of buffered data (buffer underrun) occurs, which is the case for all wireless communication terminals running the media player 110. In some cases, some of the users stop playing the content, so that the load on the wireless communication network can be reduced.

When the limit value for deceleration in data reception is set (S301), the data transmitting / receiving unit 112, as described above, receives the limit value while the streamed media data is received and decoded and outputted. It may be a limit value adjusted according to the usage status, etc. To perform the operation illustrated in FIG. 3B for deceleration according to (S302), for performing the operation, the media data read through the communication socket 22 is performed. The value of the unprocessed data amount, that is, the buffering amount, which has not been provided to the media processing unit 111 yet accumulated in the receiving buffer 113a to which S is moved is continuously monitored (SS31). Here, the value for the buffering amount may be the size of the buffered data or the length of time required to play the size, as described above, hereinafter abbreviated as "buffering value".

When the buffering value is confirmed, the data transmitting / receiving unit 112 compares the value obtained by adding a predetermined width to the value and the limit value set by the receiving control unit 113 (SS32). The margin width is a value set to prevent frequent data movement from the communication socket 22, and considering the limit value and the underrun in the reception buffer 113a, it is illustrated in FIGS. 4A to 4C. As such, it is a value determined as the width which is reduced in the above limit value with sufficient margin for underrun occurrence. The result of the comparison (SS32) is any one of Figs. 4A to 4C. As shown in FIGS. 4A and 4B, when the buffering value of the reception buffer 113a is larger than the value 401 obtained by subtracting the margin width from the set limit value, the data transmission / reception unit 112 determines the communication socket 22. The operation of FIG. 3B is terminated without moving data from the reception buffer 113a to the reception buffer 113a (SS35). The operation illustrated in FIG. 3B for the deceleration according to the limit value is not performed when the current state of the wireless communication terminal corresponds to a connection switching precondition (S303). Is performed by the data transmitting and receiving unit 112 continuously or periodically until it is (SS34). Whether the current state corresponds to the connection switching precondition is determined by the reception control unit 113 and notified to the data transmission / reception unit 112, which will be described later.

During the reception control operation for deceleration according to the limit value, as illustrated in FIG. 4C, when the checked buffering value is smaller than the value 401 obtained by subtracting the predetermined allowable width from the limit value, the data transmission / reception unit ( 112 continuously reads (52a) the data blocks 51 reaching the communication socket 22 such that the buffering value of the receiving buffer 113a becomes the limit value as illustrated in FIG. The receiving buffer 113a is filled in order (52b) (SS33). When the communication socket 22 is emptied by the data transmission / reception unit 112 and the communication state of the data communication path is good, the operating system 100a immediately connects the cellular modem 1a and the It is filled with media data received through the cellular codec 1b.

As described above, since the present state is repeatedly performed unless the current state corresponds to the connection switching precondition, the communication state of the currently connected wireless communication network, for example, the cellular network 11a is good. Although it is possible to provide a sufficient data rate, the buffering value of the data buffered for decoding by the data transceiver 112 does not, on average, exceed the set or adjusted set limit. Although the communication state is good, even if the media data can be provided from the content server 12 at a service rate faster than the required rate required by the content, the communication socket 22 is full of data. After the state is established, a communication protocol for transferring between point-to-points executed in the operating system 100a, for example, data flow control of a transfer control protocol (TCP). As a result, data transmission from the remote location, that is, the content server 12 is also stopped. In addition, since the operating system 100a receives data and fills the communication socket 22 only by being moved to the reception buffer 113a and emptied by the data transmission / reception unit 112, the cellular network 11a The data transfer rate between the media player 110 and the content server 12 through the convergence to the required speed of the content, and the buffering value of the media data maintained by the media player 110 is set on average. It stays below the limit. Therefore, even if the execution of the media player 110 is interrupted during the play by the user's request or the like, the amount of data unnecessarily received by the media player 110 (the image based on the data amount is visually or audible to the user). The term "unnecessary" is used because it is not expressed.

Users who use media content sometimes watch or listen to the media content that they have requested, but in many cases, the play is stopped. If you watched the part you are curious about, you will stop playing the content without seeing the part afterwards, or after the requested content is played. As described above, if the above limit value is appropriately set, the load on the wireless communication network to be used is statistically reduced as compared with the case of buffering and playing larger.

However, in the case of using the media data by minimizing the buffering value by the limit value, if the current connection state of the wireless communication terminal 100 is switched, for example, the connection is released and reconnected or other access network, For example, when switching to the Wi-Fi network 11b, it may take a considerable time, for example, several seconds to more than ten seconds, so in this process, all the buffered data of the reception buffer 113a is the media processing unit 111. Decoding may be performed to generate an underrun, which may result in interruption of the video being viewed. Accordingly, in the present invention, the reception control unit 113 checks whether the current state corresponds to the connection switching precondition and if so, increases the buffering value of the reception buffer 113a. Will be instructed.

If the current state corresponds to the connection switching precondition (S303), the reception control unit 113 is a non-commercial equivalent to a time which is considerably more than the expected time for the connection switching, for example, about 10 seconds. Restriction information having a limit value increased to a value is set to the data transceiver 112 (S311). At this time, the data transmission / reception unit 112 is also notified about the switching value described below. Preferably, the emergency value (hereinafter referred to as "emergency limit value"), which is a limit value included in the restriction information, has a value larger than the limit adjusted by the communication status / use status as described in the above embodiments. . The emergency limit value is preferably larger than a buffering value (hereinafter, referred to as a "switch value" for this value) which the reception control section 113 determines to perform connection switching. It may have the same value as the conversion value. In the latter case, separate terms (emergency limits, conversion values) are used for the detailed description of the invention. However, in the actual implementation of the invention, a single designated value is used to increase the buffering value as described below. A conversion decision is made. The conversion value is usually a little more than the time that is expected to be spent by the connection switching (for example, 3 seconds for the switch to the Wi-Fi network, 5 seconds for the switch to the cellular network), for example, about 3 seconds. It is set to a value that corresponds to the amount of time that can be afforded. The conversion value may be assigned a different value according to the type of connection conversion to be performed (for example, switching to a cellular network, switching to a Wi-Fi network, or switching to an AP in a Wi-Fi network). The emergency limit value may be designated as a single value regardless of the type of the connection switching, but may be specified differently according to the type of the wireless communication network to which the connection is to be switched.

According to the above-described embodiment, when a limit value is not set for a specific wireless communication network, that is, the Wi-Fi network 11b, the reception controller 113 may transmit the data even if the current state corresponds to a connection switching precondition. The operation of setting the emergency limit value in the transceiver 112 is not performed. In this case, the data transmission / reception unit 112 may be notified of the switching value designated according to the connection switching type. In one embodiment according to the present invention, a limit value initially specified for a specific wireless communication network, for example, the Wi-Fi network 11b, may have a value larger than each conversion value specified according to a connection switching type. Even in this case, the reception control unit 113 does not set the emergency limit value. Of course, the switching value can also be notified at this time.

In another embodiment according to the present invention, the emergency limit value may specify a value corresponding to or greater than the maximum storage capacity of the reception buffer 113a. In this case, the data flow control according to the capacity of the storage resource is applied, and the data deceleration obligation by setting a limit within the storage capacity of the storage resource, that is, the receiving buffer 113a, is released. will be. That is, the restriction information indicating deactivation of the deceleration operation (release of the set limit value) is the same as that set in the data transmitting / receiving unit 112. In this case, in the operation illustrated in FIG. 3B, only SS33 steps without SS31 and SS32 steps are illustrated. Will perform.

According to the setting of the restriction information having the emergency limit value, the data transmission / reception unit 112 performs the reception control operation according to the emergency limit value as described above, and repeatedly performs the operation illustrated in FIG. 3B. At the same time as S312, it is checked whether the buffering value of the reception buffer 113a exceeds the notified change value (S313).

On the other hand, since the limit value has been changed to the emergency limit value, according to the process described with reference to FIG. 5, data movement from the communication socket 22 is repeatedly performed (SS33), in this case, the communication socket 22 ) Read speed is faster than before. Therefore, as illustrated in FIG. 6, in a short time, the buffering value 60 is increased to the emergency limit 61 which is greater than the conversion value 62 determined as described above (63). It is possible to prepare for the time when no data is received.

Meanwhile, the connection switching precondition checked by the reception controller 113 may correspond to reception of a network switching command from the outside. In one embodiment according to the present invention, the network switching command from the outside at this time is preferably via the cellular network 11a. The command is received from a load control server that manages the load of each service area of the cellular network 11a. In the present embodiment, the reception control unit 113 uses a communication information API for the cellular network 11a provided by the operating system 100a to specify a specific channel in a radio signal of the cellular network 11a. For example, periodically check the control signal transmitted and received through the paging channel. A base station (or a small base station) connected to an exchange station constituting the cellular network 11a (hereinafter, the term “base station” is used to include a small base station unless technically the application thereof should be excluded.) Always exchanges a radio signal of a signal format that can be received and interpreted by the cellular modem 1a / cellular codec 1b with a mobile station such as the wireless communication terminal 100. Therefore, the load control server receives the amount of traffic applied to the service area of each base station, determines whether the traffic amount is concentrated at a moment, and urgently regulates the use traffic, and the service area determined to be urgently regulated. In this case, the network switching command for the base station is transmitted to the switching center of the base station via the dedicated communication network. When the network switching command is received through the switching center, the target base station inserts the command into an appropriate position in the radio signal format and transmits the radio signal. Then, it is decoded by the cellular codec 1b of the mobile stations including the radio communication terminal 100 located in the cell of the base station and provided to the operating system 100a. Instead of the periodic confirmation, the reception control unit 113 registers with the operating system 100a to generate an event to itself when the network switching command is received. It may be confirmed that the received by (100).

Through such a process, when the reception control unit 113 receives a network switching command from the outside, the limit value is increased to the emergency limit value as described above, and is reset to the data transmission / reception unit 112 as described above. The data transmission / reception unit 112 is notified of a switch type, that is, a designated switch value corresponding to the switch to the Wi-Fi network 11b. As described above, when the checked buffering value exceeds the switching value (S313), the access network switching operation according to the received network switching command is performed (S314). This will be described in detail later.

In another embodiment according to the present invention, an execution object, for example, an application or a process, which receives the network switching command from the outside in the same manner as described above and performs the network switching accordingly, the media player 110. And can be executed separately. In the present embodiment, when the execution object receives the network switch command and performs an access network switch operation, the media player 110 notifies the media player 110 that the network switch command has been received. Such notification may be made through an information initiator, for example, an intent object, configured in accordance with an information format defined by the operating system 100a for exchanging information / commands between processes. The media player 110 notifies the reception control unit 113 of the notification of the switching of the access network. In this embodiment, since the separate execution object performs the access network switching operation, the reception control unit 113 is notified of the switching fact from the execution object in the same manner as described above with respect to the access network switching. Alternatively, by listing in the operating system 100a for an access network switching event, when the access network is switched, the switching fact may be notified from the operating system 100a. The reception control unit 113 is notified of the fact that the network is switched, because the media data that is received via the currently connected wireless communication network, even if the use network is switched so that the media data is continuously received continuously To perform the operation. This will be described later.

The connection switching precondition checked by the reception control unit 113 may correspond to a connection switching request to another wireless communication network, for example, the Wi-Fi network 11b. Of course, this request is valid only if the Wi-Fi network 11b is currently accessible, otherwise it is considered that the request does not correspond to the connection switching precondition. In order to confirm whether the Wi-Fi network 11b is accessible, the reception control unit 113 requests and receives information on the Wi-Fi network state from the operating system 100a. The operating system 100a controls the Wi-Fi modem 2a to physically search the Wi-Fi signal band for this request, after which the Wi-Fi modem 2a is the corresponding signal band. Reads identification information of each access point and a value of a received signal strength indicator (RSSI), etc. (r11 in FIG. 1B), and returns them to the reception control unit 113. If there is no access point in the returned information, the reception control unit 113 determines that the current Wi-Fi network is not accessible. Even if there is a connection point, it may be determined that the connection is not possible even when there is no connection point at which a signal of a predetermined fixed strength is received. In this case, the reception control unit 113 may notify the data transmission / reception unit 112 differently from each other according to the type of access point to which the connection is possible. For example, if an access point that is currently identified as accessible is of a type that has an authentication procedure, it will be notified by specifying a larger value than the type that does not exist. For example, if the type does not have an authentication procedure, the estimated connection time is about 3 seconds, and if the type has an authentication procedure, the estimated time is about 10 seconds. You can decide. Of course, if there is a previous connection and the types of connection points that can be connected are mixed, a long time conversion value is determined and used.

The reception control unit 113 is a request for switching to a Wi-Fi network, for example, a request notified from another execution object, or a communication environment setting provided by the main control unit 10 on the display panel 5. When there is a request from a user through a menu, an icon, or the like, or a request through a button or the like provided by the media player 110 on the display panel 5, the Wi-Fi is currently described as described above. It is checked whether the network 11b is connectable, and if it is in a connectable state, the limit value is increased as described above and the data transmission / reception unit 112 is set and notified as described above.

In the examples of the above-mentioned connection switching preconditions, the operation according to the command or the request is performed when the buffering value of the reception buffer 113a exceeds the notified conversion value. To this end, the reception control unit 113 waits until such a state is received from the data transmission / reception unit 112, and then the data transmission / reception unit 112 notifies that the buffering value has exceeded the switching value (S313). Then, the operation according to the command or request is performed (S314). If the other control is notified that the command or request has been received, the reception control section 113 is ready to switch the connection to the execution object when such a status is notified from the data transmission / reception section 112. Information indicating that the information is delivered. Of course, the actual connection switching may be made by another execution entity before such information transfer.

The connection switching preconditions checked by the reception controller 113 may also correspond to the wireless communication terminal 100 being in a mobility state. The reason why the mobility state is regarded as the connection switching precondition is that the connection IP address may be changed and assigned in the wireless communication network which is currently connected with the movement. Whether or not the wireless communication terminal 100 is in a mobile state is determined, if the GPS module is provided in the wireless communication terminal 100, by activating the GPS module and changing the position coordinates received therefrom. can do. In another embodiment according to the present invention, as described above, it may be determined from the change in signal strength with respect to any connection point of the Wi-Fi network 11b periodically checked through the operating system 100a. It may also be determined from the change of the service cell of the cellular network 11a identified through the operating system 100a. If the reception control unit 113 determines that the wireless communication terminal 100 is in a mobility state, as described above, the limiting control unit 113 may increase the limit value to the emergency limit value and reset the limiting value to the data transmission / reception unit 112. Be prepared for a switchover. In this case, the reception control unit 113 may notify the data transmission / reception unit 112 as a switching value as a value designated for switching to the cellular network 11a.

In the above-described embodiments, when the data transceiver 112 attempts to increase the buffering value of the reception buffer 113a according to the setting of the emergency limit value, the buffering value may not increase as desired. . That is, if there is current data in the communication socket 22, the data filled in the communication socket 22 by the operating system 100a as well as the data thereafter may be immediately moved to the reception buffer 113a. If the data rate filled by the reception buffer 113a and the speed at which the media processor 111 withdraws data from the reception buffer 113a are almost the same, the buffering of the reception buffer 113a is performed. The value does not increase. For example, when all the data of the communication socket 22 in a full state are read and emptied, an almost empty time between each data block refilled in the communication socket 22 during the play corresponding time of the read data amount is confirmed. If there is no time data), this means that the maximum service rate that can be provided to the wireless communication terminal 100 in the service area of the currently connected wireless communication network or in the content server 12 is the media player. This means that the content of the 110 is almost equal to the required rate of the content currently being received. (If the free time between each data block is 80%, the data transmission rate in the wireless communication area is approximately 5 times faster than the required rate. Means that. ). In this case, it is not possible to increase the buffering value of the reception buffer 113a in such a manner as to increase the amount of buffered data. Therefore, the reception control unit 113 increases the buffering value in a manner to increase the time length of the buffered data in the following manner.

A method of increasing the time length of buffered data is a content streaming service, eg live, which is provided so that the content streaming provided from the content server 12 can be changed to the same content of different quality at any point in time and subsequently received. (live) can be performed for the streaming service.

If the HTTP request transmitted by the data transmitting / receiving unit 112 is for live content, the response includes a type (quality or bitrate, etc.) or an attribute (video or audio, etc.) belonging to the live media provided for the selected item. Media index information as illustrated in FIG. 7A, which contains file list information for each of these different streams, is included, and the index information includes a list file containing file list information to be requested when each media component is selected. URL information 701, 702, 703 is described as illustrated. In addition, when one media component is selected on the selection screen according to the media index information provided by the media player 110 on the screen in a proper manner, the communication protocol for the URL information of the list file according to the selected content is applied. The request is created and transmitted to the content server 12 through the data transmission / reception unit 112, and the list file is received by the data transmission / reception unit 112 accordingly. FIG. 7B illustrates an example of information described in a received list file. The URL 711 and content play time length information of content segment files generated after a current time point for the selected live image component are shown. 712 and the like. In the name of each fragment file, a sequence number 713 is added to indicate the order. Thus, the data transmitting and receiving unit 112, analyzes the information from the file list in the received response of the first section at the present time on the list (the URL ( "segmentN .ts _k"), http: // live ... / video1 / segmentN _k .ts) is transmitted to the content server 12 through the operating system (100a), the data of the content piece of a certain play time through the communication socket Received and provided to the media processing unit 111 through the receiving buffer 113a, and having a next sequence number on the received list information before the play time of the provided data ends (" segmentN _{k +1} .ts &Quot; ) transmits a request according to a communication protocol for a URL so that subsequent reception of live video media data can be made and subsequently provided to the media processing unit 111.

When the content currently decoded and output by the media player 110 is live media, the media data is continuously transmitted through the communication socket 22 and the reception buffer 113a in the same manner as described above. As mentioned above, in spite of resetting the emergency limit value, if the buffering value of the receiving buffer 113a does not increase to the emergency limit value, the data transceiver 112 receives the In the media index information as illustrated in FIG. 7A, which is stored, media components having lower quality (lower in screen size, resolution or frames per second, quantization level, etc.), that is, lower data rates are selected. In the example of FIG. 7A, if play is currently in progress for the first media component 701, a second media component 702 having the same content as the media component but requiring a lower required speed (BANDWIDTH = 300000) is selected. Choose. If there are a plurality of video components having different required speeds, the data transmitting / receiving unit 112 selects a media component having an appropriate necessary speed in consideration of the increase rate of the reset limit value (= reset limit value / previous limit value). . For example, if the increase rate of the limit is increased by 400%, the required speed selects a media component with a required speed lower than 25% or less than the required speed of the current media component. If there is no such property in the media component of the image that has the required speed, then an audio component 703 may be selected that has content that is partially identical, ie only audio.

In the media index information, if one media component to be changed is selected in the above-described manner in the media index information, the data transmission / reception unit 112 requests and receives a list file at that time for the selected component, and then, in the list file, A request based on a communication protocol for a URL of a content fragment having a sequence number following the sequence number of the content fragment that has been requested immediately is created and transmitted to the content server 12 through the operating system 100a. 8 is a view to help understand the process. The data transmitting / receiving unit 112, in the information received from the last received (or previously stored) video list file 800, is a sequence following the sequence number N _{k-1 of the} immediately requested content piece 801 A content piece 811 having a number N _k is specified in the list file 810 received for the changed-selected media component, and a request by a communication protocol requesting the specified content piece 811 is transmitted. Done. Accordingly, after the content piece 821 that was requested to be transmitted immediately, the content piece 822 requiring a lower speed is received through the communication socket 22. Of course, later, according to the sequential fragment request as described above, fragments subsequent to the content fragment 822 are sequentially received and filled in the reception buffer 113a.

By the above-described process, if the data is switched to the media data having a lower required speed, even if data is filled in the reception buffer 113a by the same speed as the previous reception speed, the play time by the data amount is the emergency. Close to the limit value, it is possible to prepare for the connection change as described above. If the buffering value of the receiving buffer 113a is not increased by the reset emergency limit value and the quality of the received content cannot be changed, the data transmitting / receiving unit 112 determines the media processing unit 111. Notify When such a notification is received, the media processing unit 111 decodes the data as long as there is data in the reception buffer 113a, and since no more data is filled in the reception buffer 113a, a buffer underrun is generated. When generated, the media data of small size, which is preferably acquired and stored (preferably, the media data may be obtained and stored through a predetermined access address when the media player 110 starts up). Decode output. This decoding output may be repeatedly performed on the media data until the new media data is stored in the reception buffer 113a after the subsequent transfer.

According to the embodiments described above, when the data transmission / reception unit 112 increases the buffering value of the reception buffer 113a to the emergency limit value and the buffering value is equal to or greater than the notified switching value, the reception control unit ( 113), the reception control unit 113, if the previous setting to the emergency limit value was to directly perform the network switch, the access network switching process according to the notification as follows. According to an embodiment of the present invention described above, in a connection state of a specific wireless communication network, when the reset limit value is not reset or the preset limit value is designated as a spare time or more for the transition preparation, the reception control unit 113 If the above-described connection switching preconditions state is confirmed, may perform an operation for connection switching immediately.

If the wireless communication network to be switched is the cellular network 11a, a connection type for the communication network is designated to request connection to the operating system 100a. If the Wi-Fi network 11b is connected, the access point currently searched for Selects the connection point having the highest signal strength and requests the operating system 100a to connect to the connection point. In response to this request, when the access network is changed to the cellular network 11a or the Wi-Fi network 11b and a successful conversion is notified from the operating system 100a (the other executing object performs the connection switching and then executes the execution). The same applies to the notification from the individual.) That is, when the connection IP address is changed due to the connection IP address being assigned from the connection intention network, the reception control unit 113 transmits to the data transmission / reception unit 112. Request to perform the media data download in the following process. Then, the restriction information specified for the type of the switched wireless communication network (the rule for buffering specified by this restriction information may be to specify a buffering limit value as in the above-described embodiment, or indicate a buffering non-limiting value). () May be set again in the data transceiver 112 (S315).

In response to the data inheritance request, the data transmission / reception unit 112 first requests a communication protocol stored in association with the communication socket 22 to be closed by switching, for example, “http: // On the basis of the information described in the request document written according to the grammar for the URL such as “vod.airplug.com/video/movieABC.mp4”, it is possible to communicate with the content server 12 via the connected wireless communication network after the connection changeover. Create a new communication socket (23 in Figure 2) for a TCP connection. The generated communication socket 23 transmits a request modified by reflecting the total amount of media data moved from the response of the request to the reception buffer 113a so far from the response of the request. . For example, when the total amount of media data received according to the request and moved to the reception buffer 113a is 'N-1' bytes, the data of the corresponding content is transferred through the newly created communication socket 23. Send a request according to the requesting communication protocol by specifying the range from N bytes.

Accordingly, the content server 12 starts from N bytes through the switched wireless communication network, the Wi-Fi network 11b, or the cellular network 11a for the same content previously transmitted to the wireless communication terminal 100. The media data is transmitted by the Wi-Fi modem 2a and the Wi-Fi codec 2b or the cellular modem 1a and the cellular codec 1b and then transmitted to the operating system 100a. By the newly created communication socket 23 is transmitted to the data transmission and reception unit 112. Subsequently, the subsequent media data received is received by the data transmitting and receiving unit 112, and the previously received media data (the media data is extracted by the media processing unit 111 during the connection switching process. Although the data amount is reduced, the amount of data above the switching value for the connection switching is secured, so that some data in the reception buffer 113a is not drawn out until the data starts to be received through the communication network after the switching. By being stored in the reception buffer 113a, the continuity of media data is guaranteed and provided to the media processing unit 111. Accordingly, the media processing unit 111 sequentially decodes the media data stored in the receiving buffer 113a without interruption or discontinuity even when the access IP address is reassigned or the communication network used is switched. By processing, seamless continuous video and audio can be provided to the user.

If the content received and requested by the data transmission / reception unit 112 is the live content, when the data resumption request is received from the reception control unit 113, the data transmission / reception unit 112 may Based on the stored media index information as illustrated in FIG. 7A, a list file for a previously requested media component is received, and a request for a piece of content that is provided in real time at that time is performed to establish the communication socket 23. Receiving via a network allows the live stream to continue to play through the switched network or using the newly assigned access IP address after the wireless network switch.

In the above-described embodiment, when the buffering value of the reception buffer 113a is greater than or equal to the switching value, the reception control unit 113 immediately performs the connection switching process. However, in another embodiment according to the present invention, the reception buffer When the buffering value of 113a is greater than or equal to the switching value, the reception control unit 113 may display specific notification information on the display panel 5 indicating that seamless connection switching of the played content is possible. . In addition, an input item, for example, a selection (confirmation) icon or the like, which causes the user to request execution of the connection switching may be displayed on the screen together. When the reception control unit 113 provides an input item for receiving a user's switching request on the screen, when the switching request from the user is confirmed through the input item, the reception control unit 113 performs the above-described operation to switch the access. Will be performed. If only specific notification information is output on the screen, the user requests network switching through a UI for basic operation of the wireless communication terminal 100 provided by the main controller 10. Network switching may be performed by the operating system 100a.

The various methods involved in the method of decelerating the received data according to the limit described in detail in the foregoing embodiments and increasing the limit above the switch value if the current state of the terminal corresponds to the connection switching precondition are mutually compatible. If not impossible, it can be properly combined and carried out together.

Until now, a method of decelerating received data according to a limit and increasing the limit if the current state corresponds to a connection switching precondition has been performed in the wireless communication terminal. However, the method according to the present invention can also be performed by a server providing content data to a wireless communication terminal. Hereinafter, an embodiment thereof will be described.

9 illustrates the components for performing the method according to the present embodiment and the entire system in which the method is performed. The content server 200 in which the method according to the present invention is performed principally and the content server It includes any wireless communication terminal 300 to which the method by 200 is applied. In addition, the wireless communication terminal 300 includes hardware components as illustrated in FIG. 1B, and is executed based on an operating system 300a, which provides information necessary for a method performed by the content server 200. A status reporting agent 301 is provided. In addition, an AV player 302 for playing content data provided by the content server 200 is also provided for the purposes of the present invention. Of course, in addition to this, various applications, for example, a browser may be provided in the wireless communication terminal 300.

When the content server 200 provides the file data of the content requested from the wireless communication terminal 300 in a streaming manner, according to the state information of the corresponding terminal 300 reported from the status reporting agent 301. The transmission speed is appropriately controlled. The status reporting agent 301 is described in the above-described embodiments if the request by the communication protocol for requesting specific content is a specific server that the user already knows, for example, the content server 200. The content data is received from the content server 200 with respect to the information elements (type of communication network used, communication status / use status, correspondence to the connection switching precondition, etc.) for determining the buffering limit. It will be reported periodically or at that point in time with the precondition. The status reporting agent 301 may be configured to indicate an internal IP address to monitor a request according to a communication protocol transmitted by the wireless communication terminal 300 and to check whether content data is received therefrom. By assigning an IP address, for example, "127.0.0.1" or "localhost" and a port number to the status reporting agent 301, and setting a proxy for the internal IP address, the status reporting agent 301 ) Can be mediated to request / response according to communication protocol.

The content server 200 may transmit the file data of the requested content according to the information elements reported from the status reporting agent 301 before or while transmitting the file data of the requested content to the wireless terminal 300. To control. This will be described in detail below.

The content server 200 grasps the required speed Req_DataSpd at the time of play on the content data to be transmitted, and multiplies the speed by the adjustment factor a _c to the target speed Tgt_SendSpd = a _c * Req_DataSpd. The content data is read and transmitted to the wireless communication terminal 300 through a node of a connected communication network. Of course, the metadata of the content is transmitted prior to the media data of the content, and by this metadata, a specific application, for example, the AV player 302, is activated in the wireless communication terminal 300 to display the corresponding content data. Will receive. The content server 200 determines the target speed by setting the adjustment coefficient to a default value (for example, 1) until there is a report on the information elements from the status reporting agent 301. do. In the case of transmitting the content data at the target speed determined as described above, if information on a specific information element, for example, a use network type, or a communication status / use status, is received from the status reporting agent 301, FIG. 10. As described above, the adjustment coefficient is increased (1001) and maintained for a predetermined time T _hd1 . Accordingly, the speed at which the content server 200 provides content data is as high as that. The holding time T _hd1 is a buffering value for which the buffering value increased in the AV player 302 is set for the corresponding information element described in the above-described embodiment due to the increase in the transmission speed according to the change of the adjustment coefficient. It is time to make the limit. For example, if the desired buffering limit value is ThRef1, the holding time T _hd1 is determined by the following equation [3].

T _hd1 = ThRef1 / {Coefficient after change (a _{c _2} ) -Coefficient before change (a _{c _i} )} * Req_DataSpd expression [3]

Of course, in the calculation of Equation [3], Equation [2] described above is applied to convert physical quantities between time and data amount.

On the other hand, the content server 200, even if the AV player 302 starts receiving the media data, the amount of buffering generated by delaying the start of play until the desired data buffering is required is buffering. It is not reflected in the value. If there is a report on the initial buffering amount from the AV player 302, the value of the buffering amount may be reflected as the initial value of the buffering value.

In the embodiment according to the present invention, the holding time T _hd1 is made as short as possible so that the buffering value for the buffering data of the AV player 302 is as long as the desired buffering limit in a short time. However, the shorter the holding time T _hd1 is, the larger the value of the adjustment factor is, and thus the data transmission bandwidth may be a burden in the service area of the wireless communication terminal 300. In consideration of this, the holding time T _hd1 is selected as an appropriate time length.

When the holding time T _hd1 elapses, the content server 200 returns the adjustment coefficient to the pre-change value a _{c_i} as illustrated in FIG. 10 to obtain a target speed and apply it to data transmission. . Accordingly, the AV player 302 plays the content data transmitted by the content server 200 while maintaining at least content data corresponding to the buffering limit.

While this process is in progress, if another information element of the communication status / use status is reported from the status reporting agent 301, the adjustment factor is changed according to the value of the information element, and the information element The changed adjustment coefficient is maintained for a proper time so that the buffered value data corresponding to the value of Δ is buffered in the AV player 302. During this process, if it is necessary to decrease the increased buffering value due to the change of the adjustment coefficient, as shown in FIG. 11, the adjustment coefficient is changed to a value less than 1 or 0 (1101). The time T _decT of the amount (bufV _dec ) to be reduced is maintained and then returned to the default value, for example 1 (1102).

As described above, in order to appropriately adjust the buffering value of the AV player 302 executed in the terminal as desired remotely, the content server 200, when there is a difference between the required speed and the transmission speed of the content currently being transmitted. By tracking the change in the buffering value during the time the difference is maintained, the current buffering value in the AV player 302 is always known. At this time, as described above, the value buffered by the AV player 302 through the delay of the start of play may be reflected in the initial value of the buffering value, so that the value may be always known.

While the media data of the content is being transmitted to the wireless communication terminal 300 by the above process, the status reporting agent 301 informs that the status of the terminal corresponds to the above-described connection switching precondition. When the information element is received, the content server 200 changes the adjustment coefficient back to the conversion contrast value a _{c_Trans} as illustrated in FIG. 10 (1003). This conversion contrast value a _{c_Trans} is larger than the coefficient value a _{c_2} adjusted by other information elements. The holding time T _hd2 for holding the conversion contrast value a _{c_Trans} is also obtained by the following equation [4], as in the above-described equation [3].

T _hd2 = ThRef2 / {conversion value (a _{c _ Trans} ) -pre-change coefficient value (a _{c _i} )} * Req_DataSpd equation [4]

Here, ThRef2 is a value corresponding to the emergency limit described in the above embodiment. That is, when the content server 200 receives a notification that a connection changeover may occur in the wireless communication terminal 300, the content server 200 may have a buffering value sufficient to play for the time required for the switchover process. The data corresponding to) is buffered by increasing the transmission speed. The time for which data is transmitted to the wireless communication terminal 300 by the transmission rate increased by the conversion contrast value a _{c_Trans} is until the wireless communication terminal 300 terminates the current connection for connection switching. to be. Therefore, it is preferable that the holding time T _{hd2 of} the conversion contrast value a _{c_Trans} (that is, the target speed thereby) be as short as possible to be terminated before termination. Further, preferably, the holding time T _hd2 of the conversion contrast value a _{c_Trans} is shorter than the holding time T _hd1 of the adjustment coefficient value by another information element.

In another embodiment according to the invention, the conversion contrast value a _{c_Trans} may be maintained for a significant time, for example 1 minute or 2 minutes, until the connection is terminated (1011). This is because, if the connection switching preconditions are met, the possibility of a subsequent connection switching and reconnection using a new local IP address is very high. Therefore, the transmission speed increased by the value of the switching ratio is terminated by the current session. Because it will stop at the moment. Of course, if the current session is not terminated within the significant time, then after that significant time the adjustment factor is returned to the default value.

As described above, the buffering amount to the wireless communication terminal 300 is increased rapidly by the transmission rate increased by the conversion contrast value, and in this process, the buffering amount is an allowance for connection switching, that is, the above-described switching. Beyond this, a connection change can be performed by a particular app, process, or AV player 302 that has the authority to perform the connection change.

The AV server 302 of the wireless communication terminal 300 is notified that the connection has been completed or switched over, and that the data after the current buffered data is transferred using the switched wireless communication network. In this case, the content server 200 transmits the data of the requested portion of the request, starting with the default value (a _{c_i} ), as shown in FIG. 10. Depending on the process, if necessary, the adjustment coefficient is changed to adjust the target speed.

In the above-described embodiment, the type of communication network used by the wireless communication terminal 300 and the communication status / use status are received from the status reporting agent 301 executed in the corresponding terminal 300. In another embodiment according to the present invention, such information may be received through another management server capable of mutual communication with the content server 200 via a separate communication network, for example, a main communication network. To this end, the wireless communication terminal 300, through the entity running on it, for example, the AV player 302 or the status reporting agent 301, identification information of the service area currently using the data service ( This information is not only identification of the service area but also information of the type of communication network to be used.) Unique information for providing the content server 200 or uniquely identifying the wireless communication terminal 300, for example. For example, the content server 200 stores a subscriber's telephone number, a code (eg, a MAC address) assigned to a physical resource for accessing the Wi-Fi network 11b, or a code uniquely assigned to the execution entity. To provide. Such information may provide identification information on the changed area to the content server 200 whenever the wireless communication terminal 300 recognizes the change in the service area.

When the former information, that is, the identification information of the service area, is received, the content server 200 checks the type of the communication network used, and determines the value of the adjustment coefficient and the retention time of the value according to the identified type. This is reflected in the speed at which the content data is transmitted.

Then, the identification information of the received service area is transmitted to another management server, for example, a state management server monitoring a communication state or a load state for each service area of each wireless communication network, and as a response, communication for the service area. You will receive information about the status (current load, variability, etc.). When it is necessary to adjust the buffering value in the wireless communication terminal 300 additionally based on the received information on the communication state, as described above, the content server 200 sets the adjustment coefficient to a default value or more. Or change to below to maintain a certain time.

If the latter information, that is, the unique information of the wireless communication terminal 300 is received, the content server 200 receives information for communication network selection or access point selection of other management servers, for example, wireless communication terminals. It provides the received unique information to the access control server providing the. The access control server is information to be referred to when the wireless communication terminal selects one communication network among the plurality of heterogeneous networks 11a and 11b or to select one connectable access point of the Wi-Fi network 11b. In order to perform such a function, receiving the unique information of the terminal and the identification information of the service area in which the terminal is located from any wireless communication terminal that requires the selection of the communication network or the selection of the access point is mutually Since it manages in association, when the terminal unique information is received from the content server 200, as a response, identification information of the service area stored in association with the unique information is provided. When the identification information of the service area is received as described above, the content server 200 acquires the information of the communication state of the service area as described above, and based on the obtained information, the adjustment as described above. By changing the coefficient, the transmission speed is maintained for a certain time.

In addition, when the latter information is received in the form of a subscriber's telephone number of the terminal, the content server 200 provides the received subscriber's telephone number to another management server, for example, a subscriber information operation server. The subscriber requests and obtains a data service usage amount through a specific communication network, for example, the cellular network 11a. As described above, if the amount of usage determined exceeds an appropriate reference value, the content server 200, as described above, changes the adjustment coefficient (for example, the constant of the adjustment coefficient for increasing the buffering value according to the communication network type check). In order to decrease the buffering value increased by the change over time), as shown in FIG. 11, the adjustment coefficient is maintained for less than 1 time as much as the buffering value is to be reduced.

Among the aforementioned connection switching preconditions, the network switching command may be directly received from the load control server to which the content server 200 transmits the corresponding command. When the load control server transmits or before transmitting a network switching command for an arbitrary service area, it is assumed that the server (the content server 200 corresponds to such a server) is promised mutual information provision. Identification information of the area is provided as emergency control information. When the content server 200 receives the emergency control information, the content server 200 confirms whether identification information of each service area identified for wireless communication terminals providing content data is the same as identification information included in the emergency control information. If there is the same identification information, the wireless communication terminal, as described above, is changed to a conversion contrast value a _{c_Trans} to be maintained for a predetermined time or until the connected session is terminated.

Meanwhile, in the above description of the embodiments, the content server 200 increases the content data to increase the buffering value when the connection server preconditions, etc., correspond to the wireless communication terminal 300 providing the content data. Increased transmission speed of (1001,1003). However, the data rate actually increased by the content server 200 may not be supported by traffic or communication conditions on the data path, so that a buffering value as much as desired may not be secured in the wireless communication terminal 300. have. In order to confirm such a situation in advance, the content server 200 continuously monitors the actual delivery speed of the content data that it provides to the wireless communication terminal 300. 12 is an example for this.

In the transmission of content data, as illustrated in FIG. 12, an arbitrary size data block 1200 _n is delivered and an appropriate next sized data block 1200 _{n + 1} is delivered after an appropriate time point has elapsed. The transmission speed, which is the average speed according to the block transmission, is the product of the adjustment factor a _c currently applied and the required speed Req_DataSpd of the content (1201). Therefore, the content server 200, from the start time (T _tk , k = n, n + 1, ...) from the start of the transmission of the arbitrary data block to the time when the acknowledgment (Ack) for the block, Keep track of the support speed on the current communication path. Since the required time (T _tk , k = n, n + 1, ..) from the transmission start of the actual data block to the acknowledgment of the block includes the propagation delay time T _d , the content server 200 is considered a default transmission delay time, or the wireless communication terminal 300 and in a previous data transmission considering the transmission delay time identified from the response to a short data, the time required between (T _tk The transfer speeds T _k , k = n, n + 1, .. are calculated from k = n, n + 1, .. to determine the supported speed of the current data path (1202).

During this operation, if the transmission speed needs to be increased, for example, if it is notified that the state of the wireless communication terminal 300 corresponds to a connection switching precondition, the transmission speed and the monitored support rate that the mobile station should increase should be increased. Compared to each other, and if the support rate does not fall within a certain allowable range for the transmission rate to be increased, the content server 200 does not change the current transmission rate as illustrated in FIG. 13 (1301). The buffering value in the AV player 302, i.e., the playable time, is changed by 1311 by changing the content of the same content as the content being transmitted and having lower quality, or another attribute, for example, audio content. This is increased (1321). Of course, since the data transmission rate has not been changed, the size of the data buffered in the AV player 302 remains unchanged on average (1322). How much lower the quality of the content is, the required speed required for the content, the support speed on the currently known transmission path, the buffering value to increase, and the connection switching preconditions until the actual connection switching is performed. It is determined by considering the statistically expected time. Of course, after changing to content of different quality, the position of the data to be transmitted of the changed content is a position where the content following the content of the last content data previously transmitted starts. If the content being transmitted was live content, as in the above embodiment, the data of the first content piece of the list file is transmitted together with the list file for the lower quality component or the component of another attribute.

In another embodiment according to the present invention, if the monitored support rate does not fall within a certain allowable range to increase the transmission rate to be increased, the transmission rate is changed to a lower quality content. It may increase to within the supported range (1302).

In the above embodiments, the content server 200 controls the data transmission rate so that the data buffering value in any wireless communication terminal is adjusted to meet a given condition. In another embodiment according to the present invention, the adjustment of the amount of data buffering is made by an application's own algorithm, such as an AV player running on any wireless communication terminal, and the content server 200 considers adjusting the buffering value. Instead, the data transmission speed of the requested content may be controlled. In the present embodiment, according to the same method as described above, when the type of the wireless network used by any of the wireless communication terminals connected to each other is identified, the transmission rate of the requested content is based on the required speed of the content according to the identified type. Decide on For example, as illustrated in FIG. 14, if the using wireless network is the cellular network 11a, at ₁₄ times k1 times (eg, 1.2 times) the required speed PlySpd required by the content, In the Wi-Fi network 11b, the transmission rate is determined by k ₂ times (for example, 1.5 times) (preferably, k ₂ is greater than k ₁ ) of the required speed (1412). do.

In another embodiment according to the present invention, the transmission speed for the Wi-Fi network 11b may be designated as a speed higher than the conversion contrast rate described below.

When data of the content is transmitted at a transmission rate higher than the required speed of the content determined as described above, the amount of data buffering in the AV player or the like of any wireless communication terminal that receives the data is higher than the play speed PlySd. The surplus rate {(k ₁ -1) * PlySpd or (k ₂ -1) * PlySpd} increases. When the buffering amount is increased to reach the maximum buffering capacity, or whenever an appropriate buffering value set by the AV player or the like is reached, the transmission is interrupted or the data is interrupted by data flow control between point-to-point communication. Therefore, as illustrated in FIG. 14, the content data is transmitted intermittently (the space between the solid lines indicates that the data is not transmitted). However, when the data is transmitted, the data is transmitted according to the transmission rate determined according to the network. 1420). As described above, when an information element indicating that a connection switching precondition is received (1430) is received, the content server 200 is considerably higher than, for example, a transmission rate determined at the time of confirming the usage network. The data is transmitted by changing the speed (1431) of the conversion rate 3 to 5 times the speed. This high data rate increases the amount of data buffering in a short time to prepare for an actual connection change in any of the wireless communication terminals.

Thereafter, when the session connected to the wireless communication terminal, which is transmitting data at the rate of conversion, is terminated, the content server 200 stops transmitting the content and receives a re-request for the content. As described above, according to the type of wireless communication network to which the arbitrary wireless communication terminal is connected, the transmission rate is determined based on the required speed of the content and applied to the transmission of the content.

The various methods involved in the method of adjusting the transmission rate for controlling the data buffering value of the terminal in accordance with the state of the terminal in detail in the above-described embodiments are suitably combined unless they are incompatible with each other. Can be implemented together.

The content server 200 described in the above-described embodiments may be configured to include a communication processor 200a, an information processor 200b, and a content storage unit 200c, as illustrated in FIG. 15. The content server 200 may be composed of a single computing device or a plurality of computing devices that are independent of each other. When each of the components is constructed as an independent computing device, for example, a server, they are connected to each other through a dedicated line or a dedicated network, and mutual communication is performed under an appropriate network security communication protocol. Each of the components illustrated in FIG. 15, that is, the communication processing unit 200a, the information processing unit 200b, and the content storage unit 200c, performs the above-described operations performed by the content server 200 in various embodiments. They will work together.

The communication processing unit 200a is connected to a main communication network or the like to communicate with other servers through the communication network, and furthermore, the communication node connected to the cellular network 11a and / or the Wi-Fi network 11b and the period. Communication with any wireless communication terminal through a communication network or the like is performed based on an appropriate protocol. In one embodiment according to the present invention, as described above, at the time of data transmission through the currently established session, a function of identifying the support speed of the path and reporting it to the information processing unit 200b is also performed. It also manages logical objects for communication, such as sockets and / or sessions, for information exchange with other servers or any wireless communication terminal.

The content storage unit 200c stores a content file to be provided to the terminal and various protocol documents related to the provision thereof in a physical storage space managed by the content storage unit 200c.

The information processing unit 200b analyzes the request according to the communication protocol received from the communication processing unit 200a, searches for and finds the data or information necessary for the response in the content storage unit 200c, and then finds the data. Alternatively, the response document is constructed using the information, and the response document is provided to the wireless communication terminal that has transmitted the request through the communication processing unit 200a. If the response provided is media data of the content, as described above, the transmission rate control operation of the media data is performed. Of course, the above-mentioned information elements required in this process are transmitted through the communication processing unit 200a from an entity (for example, the status reporting agent, an AV player, etc.) executed in the corresponding terminal or from another management server. It is used for adaptive speed determination of data. As described above, the above speed determination is for adjusting the buffering value suitable for the current state of the wireless communication terminal. For this purpose, each client (terminal or execution object in the terminal) currently connected to the communication is individually A value for identification is received from the communication processing unit 200a to continuously monitor each client identification value and a buffering value that changes according to transmission rate adjustment. In another embodiment according to the present invention, the control of the actual data rate may be performed accordingly by the communication processing unit 200a by a command from the information processing unit 200b. At this time, of course, monitoring of the current buffering value of each client is performed by the communication processing unit 200a. According to another embodiment of the present invention, the information processing unit 200b may perform the transmission rate control method described with reference to FIG. 14.

The above description of each of the components 200a, 200b, and 200c of the content server 200 configured as illustrated in FIG. 15 is only for basic matters in the concept and spirit of the present invention. However, the operation of each of the components 200a, 200b, and 200c is not limited to the above description, and each of the components 200a, 200b, and 200c may be the content server according to the various embodiments described above. The operation (for example, the quality change of the content to be transmitted, etc.) of 200 may be distributed and performed in a form corresponding to each allocated function. Accordingly, operations of the components 200a, 200b, and 200c are not limited to the details described with reference to FIG. 15, but parts of the operations of the content server 200 described in the above-described various embodiments. Of course it is extended to.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. , Alteration, substitution, addition, or the like.

1a: cellular modem 1b: cellular codec
2a: Wi-Fi modem 2b: Wi-Fi codec
4: Display driver 5: Display panel
6: Input control unit 6a: Touch sensor
6b: Keypad 7: Memory
10: main control unit 11a: cellular network
11b: Wi-Fi network 12: Content server
21 _k , 22, 23: Communication socket 100: Wireless communication terminal
100a: Operating system (O / S) 110: Media player
111: media processor 112: data transceiver
113: reception control section 113a: reception buffer
113b: transmission buffer 200: content server
200a: communication processor 200b: information processor
200c: content storage unit 300: wireless communication terminal
300a: operating system (O / S) 301: status reporting agent
302: AV player

Claims (34)

A wireless communication terminal capable of accessing a plurality of wireless communication networks,
If the set restriction information specifies a limit value, a reception unit for receiving the media data from an external server while buffering the media data below the limit value through the connected wireless communication network, and providing the buffered media data to a processing unit for decoding processing. Wow,
Configured to select the restriction information specified for the type of the connected wireless communication network from the restriction information specified for the plurality of wireless communication networks, and set the restriction information, and set the limit value before the connection of the wireless communication terminal is switched. It is configured to include a control unit configured to set to the receiving unit by changing a larger emergency value,
The restriction information specifies different buffering rules for a first communication network and a second communication network among the plurality of wireless communication networks, and a buffering rule for the first communication network includes a buffering rule for the second communication network. When applied, the limit value is specified as a value less than an upper limit that buffers the media data received by the receiver below.
The first communication network is a wireless communication network having a wide service area,
And wherein said second communication network is a wireless communication network providing data services for areas limited to a distributed service area. delete The method of claim 1,
And the control unit is further configured to change and reset the limit value set in the receiving unit according to a communication state of the connected wireless communication network. The method of claim 3, wherein
The control unit may change the limit value to a smaller value when the load of the connected wireless communication network is greater than or equal to a predetermined reference value, or change the limit value to a larger value when the variability of the connected wireless communication network is greater than or equal to the reference value. And reconfigure the receiver. The method of claim 1,
The control unit, if the data amount using the data service of a specific wireless communication network of the plurality of wireless communication network is more than the reference amount, the receiving unit as a limit of a value lower than the limit specified to set for the connected wireless communication network And configured to set on. The method of claim 1,
And the control unit is further configured to set the receiving unit as a limit value different from a limit value specified for setting the connected wireless communication network when the server that transmits the media data corresponds to a predetermined specific server. terminal. The method of claim 1,
The control unit is configured to change the limit value to the emergency value when the state of the wireless communication terminal corresponds to a connection switching precondition.
In the connection switching preconditions,
Receiving a command for requesting to switch to a specific wireless communication network among the plurality of wireless communication networks from outside;
When a new wireless communication network other than the connected wireless communication network becomes accessible;
And at least one of when the wireless communication terminal is in a mobility state. The method of claim 1,
The control unit is further configured to attempt to switch the connection of the wireless communication terminal when the buffering value for the media data of the receiving unit is greater than or equal to the conversion value.
And the conversion value is greater than at least one of the respective limits specified in the different buffering rules and is less than or equal to the emergency value. The method of claim 8,
The controller may provide information on the screen of the wireless communication terminal, indicating that the connection can be switched, before attempting to switch the connection, and then when the request for connection switching is made through the user interface of the wireless communication terminal. And attempt to switch the connection. The method of claim 1,
The control unit is further configured to notify the execution object executed in the wireless communication terminal when the buffering value for the media data of the receiver is greater than or equal to the conversion value.
And the conversion value is greater than at least one of the respective limits specified in the different buffering rules and has a value less than or equal to the emergency value. The method of claim 8 or 10,
And the switching value may be designated as a different value depending on the type of wireless communication network to be newly connected or the type of connection point to be newly connected by the switching of the connection. The method of claim 1,
When the limit value is changed and set to the emergency value, the receiver is connected to a socket through which the media data is transferred from an operating system of the wireless communication terminal until a buffering value of the media data corresponds to the emergency value. And repeating reading of the socket by increasing a reading speed. The method of claim 1,
The reception unit, when the limit value is changed and set to the emergency value, performs operation of changing and receiving the media data having the characteristics that are at least partially identical to the received media data but have a lower required speed. A wireless communication terminal further configured to perform. 14. The method of claim 13,
The control unit controls the receiving unit when the transmission speed of the media data in the wireless communication area is insufficient to increase the buffering value of the media data to the emergency value, thereby requiring media data having a lower required speed. Wireless communication terminal to receive. The method of claim 1,
And the control unit is further configured to, upon the change of the connection, reset the restriction information specified for the type of wireless communication network newly connected to the receiving unit. 16. The method of claim 15,
When the connection is switched, the receiving unit transmits a request based on a communication protocol requesting data from a point subsequent to the media data received from the previously connected wireless communication network to the external server through the newly connected wireless communication network. And subsequently receive the media data while buffering the media data according to the buffering rule specified by the reset restriction information. 16. The method of claim 15,
The switching of the connection is a switching between the plurality of wireless communication networks or reconnection in the same wireless communication network. The method of claim 1,
And the emergency value is a value equal to or greater than a value corresponding to the maximum bufferable amount of the media data of the receiver. The method of claim 1,
And the upper limit is a value smaller than the maximum bufferable amount of the media data of the receiver, which is designated as the limit in the buffering rule for the second communication network. The method of claim 1,
The buffering rule for the second communication network designates a non-limiting limit of buffering by the receiving unit, and the upper limit corresponds to a maximum buffering amount of media data of the receiving unit. The method of claim 1,
And the control unit is configured not to change and set the limit value to the emergency value even before the connection of the wireless communication terminal is switched, when the connected wireless communication network is a predetermined specific wireless communication network. In the method for the wireless communication terminal to receive media data from a remote server via a wireless communication network,
Checking a type of a wireless communication network connected for data communication with the remote server and setting restriction information specifying a buffering rule for the type;
Receiving the media data provided from the remote server while buffering the data below the limit specified as the buffering rule;
Confirming whether the wireless communication terminal is in a pre-state before performing the connection switching, and if it is in the state, changing and setting the limit value to a larger emergency value;
Receiving media data from the remote server and increasing its buffering value to the emergency value;
The restriction information specifies different buffering rules for the wireless communication network and another wireless communication network, and the buffering rule for the wireless communication network is based on reception of media data when the buffering rule for the other wireless communication network is applied. The limit is specified as a value less than the upper limit to buffer below.
The wireless communication network is a communication network having a wide service area,
And wherein said other wireless communication network is a communication network providing data service for areas restricted to a distributed service area. 23. The method of claim 22,
The limit value specified in the restriction information is changed based on the communication state of the connected wireless communication network, the amount of data using the data service of the specific wireless communication network of the wireless communication terminal, or whether the remote server belongs to a predetermined server. And receiving the media data in preparation for a connection change, further comprising the step of setting. A program supply apparatus for providing a program stored in a storage space through a communication network,
Communication means capable of transmitting and receiving data to and from the outside via communication,
And a storage unit for storing an application to be executed in the wireless communication terminal, the application being transmitted through the communication unit,
The application, when executed in the wireless communication terminal,
A function of checking a type of the connected wireless communication network and selecting restriction information designated for the identified type from restriction information respectively designated for a plurality of wireless communication networks;
If the selected restriction information designates a limit value, the media data is received from an external server while buffering the media data below the limit value through a connected wireless communication network and provided to a processing unit for decoding the buffered media data. Function,
And a program structure for performing a function for changing and setting the limit value to a larger emergency value before the connection of the wireless communication terminal is switched,
The restriction information used by the application specifies different buffering rules for a first communication network and a second communication network among the plurality of wireless communication networks, and a buffering rule for the first communication network is the second communication network. The limit is specified as a value smaller than an upper limit that buffers the media data upon receiving the buffer when the buffering rule is applied.
The first communication network is a wireless communication network having a wide service area,
And wherein said second communication network is a wireless communication network providing data services for areas limited to a distributed service area. In the method for transmitting media data from a server to a wireless communication terminal through a communication network,
After transmitting the media data to the wireless communication terminal at a first data rate so that the data buffering in the wireless communication terminal increases by a first limit value specified for the type of first wireless communication network to which the wireless communication terminal is connected; Lowering the transmission speed of the media data to the second data rate;
If information indicating that the wireless communication terminal is in a pre-state before performing connection switching is received, the data buffering at the wireless communication terminal is increased faster than the first data rate so that the data buffering in the wireless communication terminal is increased to an emergency value larger than the first limit value. Transmitting the media data at a third data rate;
When the wireless communication terminal requests the transmission of the media data through a second wireless communication network, the media data is transmitted to increase the data buffering in the wireless communication terminal by a second limit value specified for the type of the second wireless communication network. Including three steps to adjust the speed,
And the first limit value and the second limit value have different sizes when the first wireless communication network and the second wireless communication network are different types. 26. The method of claim 25,
And wherein the second data rate corresponds to a decoding rate required when the media data is played. 26. The method of claim 25,
Transmit the media data for a predetermined time by changing to a data rate different from the second data rate based on the communication state of the first wireless communication network or the amount of data using a data service of a specific wireless communication network of the wireless communication terminal. And then changing the transmission rate back to the second data transmission rate. 28. The method of claim 27,
And transmitting information about the amount of data using the communication state or data service from the wireless communication terminal or another server in preparation for a connection changeover of the terminal. 26. The method of claim 25,
The information indicating that the wireless communication terminal is in a pre-state before performing connection switching is received from the wireless communication terminal or another server,
The above information to inform you that you are in the pre-state,
Information indicating that the wireless communication terminal should be switched to a specific communication network;
Information indicating that a new wireless communication network other than the connected first wireless communication network is in an accessible state;
And at least one of information indicating that the wireless communication terminal is in a mobility state. 26. The method of claim 25,
Measuring the speed supported on the transmission path to the wireless communication terminal while transmitting the media data at the second data rate,
In the second step, if the measured support rate is less than the third data rate, the media data has at least partially the same content as the transmitted media data but the required speed is changed to media data having a lower characteristic. And transmitting the media data while preparing for connection changeover of the terminal. 31. The method of claim 30,
In the second step, when the media data is changed and transmitted, the changed media data is transmitted at a rate higher than the second data rate within the measured support rate. The media data transmission method in preparation for the connection change of the terminal. An apparatus for providing media data to a wireless communication terminal through a communication network,
A communication processing unit connected to a communication network and configured to transmit media data to the wireless communication terminal, and configured to receive information regarding a state of the wireless communication terminal through the communication network with the wireless communication terminal or another device;
And control the communication processing unit so that the media data of the content selected by the request from the wireless communication terminal is transmitted through the communication processing unit, and the transmission rate of the media data is adaptively adjusted according to the information about the state. It is configured to include an information processor,
The information processing unit,
If the information about the state indicates the type of wireless communication network to which the wireless communication terminal is connected, the data buffering in the wireless communication terminal increases by the first limit value specified for the type of wireless communication network; The transmission speed of the processing unit becomes the first data rate, and then the transmission rate is lowered to the second data rate,
In addition, if the information on the state indicates the pre-state before the wireless communication terminal performs connection switching, the communication processing unit to increase the data buffering in the wireless communication terminal to an emergency value larger than the first limit value. And provide a media data in preparation for a connection changeover of a terminal, wherein the transmission rate of the terminal is configured to be a third data rate faster than the first data rate. In the method for transmitting media data from a server to a wireless communication terminal through a communication network,
Receiving a content request from the wireless communication terminal;
Determining the transmission rate for the requested content as the first transmission rate when the wireless communication terminal is connected to the first wireless communication network;
Transmitting the media data of the requested content to the wireless communication terminal by maintaining the transmission rate determined in the step 2 for a predetermined time;
If the information indicating that the wireless communication terminal is in a pre-state state before performing the connection switching is received while transmitting the media data to the wireless communication terminal, the data of the content as the conversion ratio faster than the determined first transmission speed. Including four steps to send,
In the second step, when the wireless communication terminal is connected to a second wireless communication network of a different type from the first wireless communication network, determining the second transmission speed for the content is faster than the first transmission speed. Including more,
The first transmission rate and the second transmission rate are determined based on a data rate required for playing the content, all of which are determined to be faster than the data rate, and the conversion rate is the first transmission rate. Has a value faster than at least one of a speed and the second transmission speed,
The first wireless communication network is a communication network having a wide area service area,
And wherein said second wireless communication network is a communication network providing data service for areas limited to a scattered service area in preparation for a connection changeover of a terminal. An apparatus for providing media data to a wireless communication terminal through a communication network,
A communication processing unit connected to a communication network and configured to transmit media data to the wireless communication terminal, and configured to receive information regarding a state of the wireless communication terminal through the communication network with the wireless communication terminal or another device;
And control the communication processing unit so that the media data of the content selected by the request from the wireless communication terminal is transmitted through the communication processing unit, and the transmission rate of the media data is adaptively adjusted according to the information about the state. It is configured to include an information processing unit,
If the information processing unit indicates that the connection communication network type of the wireless communication terminal is a first wireless communication network, the communication processing unit transmits the media data by maintaining a first transmission rate for a predetermined time. And if the information on the state indicates a pre-state before the wireless communication terminal performs connection switching, cause the communication processing unit to transmit the media data at a conversion ratio faster than the first transmission rate. To send,
If the information on the state indicates that the type of the connection communication network of the wireless communication terminal is the second wireless communication network, the communication processing unit maintains the second transmission speed faster than the first transmission speed for a predetermined time. Transfer media data,
The first transmission rate and the second transmission rate are determined based on a data rate required for playing the content, all of which are determined to be faster than the data rate, and the conversion rate is the first transmission rate. Has a value faster than at least one of a speed and the second transmission speed,
The first wireless communication network is a communication network having a wide area service area,
And wherein the second wireless communication network is a communication network providing data service for areas limited to a scattered service area, in preparation for switching of a terminal.

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