JP3478259B2 - Stream relay control device, stream relay control system, stream relay control method, and recording medium recording the method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stream relay control technique for efficiently realizing a large-scale stream distribution network, and more particularly, to a large-scale stream distribution efficiently and then a distribution status for each client. Stream relay control device capable of collecting and quality control
The present invention relates to a stream relay control system, a stream relay control method, and a recording medium recording the method.

[0002]

2. Description of the Related Art Conventionally, in the case of stream distribution on the Internet, generally, a stream setting protocol for requesting and setting stream contents, a stream distribution protocol for distributing stream contents based on the setting, and distribution. A stream control protocol is used for notifying the distribution status and distribution quality of the inside stream content packet and for notifying the connection state between the server and the client.

IETF (Internet Engineering Task Fo)
The protocol specified by rce) is RTSP (Rea
l Time Streaming Protocol: RFC2326, RTP (Real
-Time Transport Protocol: RFC1889) and RT
CP (RTP Control Protocol: RFC1889) is an example.

Also, when stream distribution is performed using a protocol other than these, a protocol substantially having the above function is used. Examples include Microsoft's MMS protocol, Real Network's RDT, and PNA protocol.

Since these protocols are basically supposed to be exchanged on a one-to-one basis between the server and the clients, the same stream content can be sent to a large number of clients. However, it was difficult to deliver the data efficiently. Moreover, when attempting to deliver efficiently, it has been impossible to manage the state of the client receiving the stream content and the delivery quality.

Here, the conventional stream distribution technique will be described with reference to FIGS. 8 and 9. FIG. 8 is a diagram showing a configuration example of a conventional stream distribution network. In this example, the stream server 100 and the clients 300a-
300d, connection lines 400a to 400h, transfer device 50
It is composed of 0a to 500d. FIG. 9 is a diagram showing a sequence example of a stream control protocol exchanged between the stream server and the client.

In the case of a broadcast stream distribution called a live stream distribution, a client that makes a reception request makes a distribution request for stream contents to a stream server using a stream setting protocol. In this example, the clients 300a and 300b make a request for receiving the same live stream content to the stream server 100, and the stream server 100 that has received this request sets distribution according to the request. The stream contents are distributed using the stream distribution protocol. Streaming,
The stream server and the client use the stream control protocol to confirm the delivery status of the stream content.

As shown in the sequence example of FIG. 9, the stream server 100 sends messages a and b to the clients 300a and 300b, respectively. The messages a and b are sent to each client via the connection line and the transfer device. Based on the sent message, each client measures information such as the reception status of the stream packet, the discard rate and the number of discards, and packet fluctuations at the client, and sends it to the stream server 100 as messages c and d. To do. With the sequence of these protocols, the stream server 100 can grasp the distribution information to each client and confirm the connectivity.

When the messages c and d from the client do not arrive at the stream server 100, the delivery to the client may be stopped. Also, the distribution status information from the client may be used by the stream management server as the statistical information of the stream distribution status.

When such a delivery method is adopted, the stream server 100 concentrates delivery request processing, delivery control processing, and stream content delivery processing, and as a result, large-scale live stream delivery is performed. Was difficult.

As a method of reducing the stream content distribution processing for the above problems, there is a method using a transfer technique called IP multicast. This is to transfer a stream content packet to be distributed by using IP multicast.

In this case, the stream server sends only one stream content packet regardless of the number of clients requesting reception. One stream content packet sent from the stream server is copied and transferred by the multicast compatible router or the multicast compatible switch according to the transfer route of IP multicast, and transferred to the delivery destination client. As a result, the stream content distribution processing in the stream server is reduced, and efficient one-to-many distribution can be performed.

However, when such a transfer technique is used, since one-to-many distribution is performed, it becomes difficult to perform one-to-one state control / management using the stream control protocol. In particular, ATM (Asynchronous Transfer Mode)
When attempting to perform IP multicast distribution using a distribution network that performs a one-way p-mp distribution path such as the above, the control protocol response message from the client cannot be transferred using this path, so message transfer is performed. It is necessary to prepare a separate path for this, which complicates route management. Also, even though the stream server is sending only one stream packet,
If multiple control protocol messages arrive from the client, a state mismatch may occur.

In order to solve these problems, when using multicast in live stream distribution, a method that does not use a stream control protocol may be adopted. In this case, since the stream receiving side cannot grasp the stream reception status at the client,
It was not possible to collect / manage statistical information by the stream management server that has been used conventionally.

[0015]

As described above, in the conventional stream distribution technique, since the distribution setting, the distribution management, and the stream distribution are performed between the stream server and the client on a one-to-one basis, a large-scale live stream is required. When attempting distribution, there is a problem that the processing load is concentrated on the stream server, and the bandwidth of the connection line is wasted.

Further, in order to solve such a problem, when the IP multicast technology is applied to reduce the stream distribution processing load at the server and to effectively use the bandwidth of the connection line, the application of the stream control protocol is not possible. It will be difficult. If the delivery mode that does not use the stream control protocol is used, another problem arises in that the delivery status to the client acquired by the protocol cannot be collected.

An object of the present invention is to solve the above-mentioned problems, to efficiently perform large-scale stream distribution, and to collect the distribution status of each client and to perform quality control. An apparatus, a stream relay control system, a stream relay control method, and a recording medium recording the method.

[0018]

In order to achieve the above object, a stream relay control device of the present invention is (a) a stream relay control device in a stream distribution network, which receives a packet sent from a stream server. The means (401, 201a), the means (202) for analyzing the header information of the packet and identifying the stream control protocol, and the packet
Or means for transferring to a plurality of delivery destinations (204, 20
5,207,208,211,212,213,40
2, 403) and means for notifying the packet information when the packet is a stream control protocol (20
2) and means (203) for acquiring the status information and / or the identifier of the stream server from the packet information.
And a means (206) for creating a response packet for the packet and transferring it to the stream server.

(B) In the stream relay control device of (a) above, further, a means (207) for rewriting the server information and / or the identifier in the packet information sent from the stream server, and the packet It is characterized by comprising means for transferring to one or a plurality of distribution destinations.

Also, (c) means (402, 403, 201b) for receiving a packet sent from the client or a device having a client function, and the header control information of the packet are analyzed to obtain a stream control protocol. And a means for acquiring the packet information.

(D) In the stream relay control device of (c) above, a client or
Means (209) for accumulating stream control packet information sent from a device having a client function, and means (210) for responding to a request from the stream management server.
It is characterized by having.

Further, the stream relay control system of the present invention is characterized by having (e) the stream relay control device of the above (a) and the stream relay control device of the above (c).

Further, it is characterized in that (f) the stream relay control device of the above (b) and the stream relay control device of the above (d) are included.

Further, the stream relay control method of the present invention is (g) a stream relay control method in a stream distribution network, which comprises a step of receiving a packet sent from a stream server, analyzing the packet information, and a stream A step of identifying that the packet is a control protocol, transferring the packet to one or more delivery destinations, and then notifying the stream control protocol processing unit (SCP) of the packet information, and a stream from the packet information. The method is characterized by including a step of acquiring the status information and / or the identifier of the server and a step of creating a response packet for the packet and transferring the response packet to the stream server.

(H) In the stream relay control method of (g), further, the server status information and / or the identifier of the packet information sent from the stream server is rewritten so that one or more of the packets can be transmitted. It is characterized by having a step of transferring to a delivery destination.

Further, (i) a stream relay control method in a stream distribution network, which comprises a step of receiving a packet sent from a client or a device having a client function, analyzing the packet information, and a stream control protocol. And a step of acquiring the packet information.

In the recording medium of the present invention, (j) the processing steps for realizing the stream relay control method according to any one of (g) to (i) above are recorded as program codes. Is characterized by.

According to the present invention, by adopting the above configuration, the stream control protocol message sent from the stream server is appropriately delivered to the client receiving the stream content, and
Since the stream server can respond to the message, it is possible to efficiently perform large-scale stream distribution while reducing the server processing.

In addition, a stream relay control device analyzes a stream control protocol packet sent from a client or a device having a client function, collects statistical information, and responds to a collection request from a stream management server. Therefore, it is possible to perform the large-scale stream distribution by using the one-to-many transfer technology such as IP multicast after grasping the client distribution status using the stream control protocol.

By using the recording medium of the present invention, the present invention can be widely distributed in the market.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described in detail below with reference to the drawings. (First Embodiment) A stream relay control device having a stream control protocol processing function from a stream server and a stream relay control having a stream control protocol processing function from a client, which are the first embodiment of the present invention. A stream relay control system including a device will be described with reference to FIGS. 1 and 2.

FIG. 1 is a diagram showing a configuration example of a stream distribution network service system according to the first embodiment of the present invention. In the first embodiment of the present invention, as shown in FIG. 1, a stream server 100 and a client 30 are provided.
0a to 300d, connection lines 400a to 400h, transfer device 500, and means for analyzing the stream control protocol sent from the stream server, means for transferring the packet to one or more delivery destinations, and the stream control protocol. A stream relay control device 200a having means for creating a response packet to the packet and transferring it to the stream server, and a stream relay control device having means for analyzing a stream control protocol packet sent from a client or a device having a client function. It is characterized by being composed of 200b and 200c.

Here, for example, the stream server 10
0, the stream relay control device 200a, and the client 3
00a and the stream relay control device 200b are directly connected through a connection line, but this is merely an example, and there is no problem even if a transfer device such as a router is used.

FIG. 2 is a diagram showing a main functional block configuration of the stream relay control device 200 according to the first embodiment of the present invention. The stream relay control device 200 according to the first embodiment of the present invention, as shown in FIG. 2, has line termination units 201a and 201b, a packet distribution unit 202, a control packet analysis unit 203, and a stream packet analysis unit 2.
04, route selection unit 205, response packet generation unit 206,
The packet rewriting processing unit 207, the reading control unit 208, the writing processing unit 211, the common memory 212, the reading processing unit 213, the packet buffer 214, and the lines 401 to 403 are featured. The control packet analysis unit 203 and the response packet generation unit 206 make up a stream control protocol processing unit SCP.

The flow of the stream control protocol packet processed by the present invention will be described with reference to the sequence diagram of FIG. 3, and the processing in the stream relay control device will be described according to the block configuration of FIG. It should be noted that in this description, the stream content that the client has already requested to receive has been set by using the stream setting protocol, and the stream distribution protocol is being used for stream distribution. I am assuming. FIG. 4 is a diagram showing an example of contents of the stream control protocol packet in the present description.

(Processing of Packet 10 in Stream Relay Control Device 200a) First, the stream control protocol packet 10 is transmitted from the stream server 100.

In the stream relay control device 200a, the line 401 receives the signal, and the line terminating unit 201 terminates the packet. Next, the packet distribution unit 202 analyzes the packet information, identifies that it is a stream control protocol, and transfers the packet to the write processing unit 211.

Note that the header information of the packet is used as the information for determining whether the packet is a stream control protocol packet. For example,
When RTCP defined by IETF is used as a stream control packet, it is known to use a port number that is one larger than the UDP port number used in RTP which is a stream distribution protocol. Therefore, in the packet distribution unit 202, the UDP of the packet
It suffices to analyze the port number and determine if it is that value.

After the packet 10 is transferred to the write processing unit 211, the packet information is transferred to the control packet analysis unit 2
03 and the stream packet analysis unit 204.

Packet 1 transferred to the write processing unit 211
0 is stored in the common memory 212. At this time, the route selection unit 205 performs route selection based on the packet information notified to the stream packet analysis unit 204, and stores it in the packet buffer 214 corresponding to the destination according to the selection result. When there are a plurality of clients, they are duplicated and stored in a plurality of packet buffers 214.

Alternatively, p-m such as IP multicast
When transmitting the packet 10 using p-distribution, the destination IP address is rewritten to the corresponding IP multicast address and the packet 10 is stored. In this example, p-mp distribution is used.

Next, according to the read time managed by the read control unit 208, the read processing unit 213 transfers it to the line terminating unit 201 and sends it out via the line 402.

The control packet analysis unit 203 analyzes the packet transferred from the packet distribution unit 202, and as shown in FIG. 4, since it is a Sender Report message, the stream control sent from the stream server is controlled. Identify it as a packet. Further, the sender identifier is analyzed to extract that the sender of the packet is the stream server 100.

Next, the response packet generation unit 206 is notified of the above analysis result, and the response packet generation unit 205 generates the response packet 11 for the server 100. In this example, Receiv, which is an identifier indicating that the packet is a response packet.
er Report, 200a as sender identifier, Sender Repo
rt (SR) 10 as the sender identifier according to the analysis result
0, discard rate 0 as distribution status information, response packet 11
To store. Next, it is stored in the common memory 212 via the packet rewrite processing unit 207. At that time, the server 10
Packet buffer 21 corresponding to the destination transferred to 0
Store in 4. Then, the data is sent to the line according to the read time managed by the read control unit 208.

(Processing of packet 10 in stream relay control device 200b) The packet 10 sent from the stream relay control device 200a arrives at the stream relay control device 200b via the transfer device 500.

In the stream relay control device 200b, similar to the process of the packet 10 in the stream relay control device 200a, the packet is processed via the write processing unit 211.
It is stored in the common memory 212. In this example, when transferring to multiple clients, IP multicast is not used,
Since IP unicast is used, multiple copies are made and stored in the packet buffer 214 corresponding to the corresponding destination.
It is sent to the line according to the read time managed by the read processing unit 208.

In the stream relay control device 200b,
Since the stream server 100 is connected not directly but through the stream relay control device 200a, the packet 10 is not analyzed and the response packet generation process is not performed.

(Packet 1 in stream server 100)
Process 1) The packet 11 sent from the stream relay control device 200a arrives at the stream server 100 via the line 400a.

The stream server 100 analyzes the packet 11 and recognizes that it is a response packet to the packet 10 sent by the stream server 100, and the connectivity to the stream relay control device 200a is maintained. It recognizes that the stream content being distributed is distributed to the stream relay control device 200a without loss. As a result, the stream of the stream content is continuously delivered.

(Processing of packet 10 at client)
The packet 10 sent from the stream relay control device 200b arrives at the clients 300a and 300b via the lines 400e and 400g.

The client 300a analyzes the packet 10 and sends the packet to the Sender Report.
And the response packet 12 for the packet is created.

In this example, it indicates that the packet is a response packet.
Receiver Report, 300a as sender identifier, Sende
r Report (SR) 100 is stored in the response packet 12 as the sender identifier according to the analysis result, and the discard rate 0.01 as the distribution status information. Next, the response packet 12 is sent to the stream relay control device 200b via the line 400e.

Similarly, the client 300h generates the response packet 13 and sends the response packet 13 to the stream relay control device 200b via the line 400f.

(Processing of Packets 12 and 13 in Stream Relay Controller 200b) Clients 300a and 30
The packets 12 and 13 sent from
e, 400g, the stream relay control device 200
Arrive at b.

In the stream relay control device 200b, as a result of the packet analysis processing in the packet distribution unit 202, the packet information is notified to the control packet analysis unit 203, and then the analysis processing of the packets 12 and 13 is performed. Recognizes that the packet is a response packet to the packet 10 sent by the stream relay control device 200b, and recognizes that both the clients 300a and 300b have connectivity.

It should be noted that the packet 1
When the response packets 11 and 12 for 0 do not arrive, it is determined that the connectivity with the client that is supposed to send the packets that did not arrive is interrupted, and the distribution of the stream content is stopped or the stream session is disconnected. It is possible to perform the above processing from the stream relay control device side. Further, after analyzing the packets 12 and 13, it is not necessary to transfer them to the upstream stream relay control device, and the stream relay control device 200b may discard them.

According to the first embodiment described above, there is a one-to-one correspondence between the stream server and the stream relay control device, and between the client or the device having the client function and the stream relay control device by using the stream control protocol. After confirming the connectivity, it is possible to efficiently realize the one-to-many large-scale stream distribution. In particular, as a distribution network between stream relay control devices,
It is possible to use one-way p-mp distribution of ATM. Further, since it is not necessary to transfer the stream control protocol packet between the stream relay control devices, it is not necessary to reduce wasteful packet processing or secure a route for packet transfer.

(Second Embodiment) A stream relay control device 200 according to an embodiment of the present invention is a stream relay control device having a stream control protocol processing function from a stream server, which is a second embodiment. A stream relay control system including a stream relay control device having a stream control protocol processing function from a client and an information storage function, and a stream management server will be described with reference to FIGS. It should be noted that the description of the part that performs the same processing as that of the above-described first embodiment may be omitted.

FIG. 5 is a diagram showing a configuration example of a stream distribution network service system according to the second embodiment of the present invention. In the second embodiment of the present invention, FIG.
In addition to the above configuration, the stream management server 600 having a function of managing the distribution status to the client and the like, and the connection line 400i for connecting to the stream relay control device
It is characterized by being composed of 400k. Here, the stream management server and the stream relay control device are connected, but a configuration in which the stream server and the stream management server are connected in order to manage the distribution status of the stream server and the like may be used.

FIG. 6 is a diagram showing a main functional block configuration of a stream relay control device 200 according to the second embodiment of the present invention. The stream relay control device according to the second embodiment of the present invention has an information storage that stores a statistical information table 209a in addition to the configuration of the stream relay control device according to the first embodiment shown in FIG. Part 20
9. It has a management server response generation unit 210.

Regarding the flow of stream control protocol packets processed according to the second embodiment of the present invention, the processing of the packets 12 and 13 in the stream relay control device 200b which is a difference from the first embodiment. explain.

(Processing of Packets 12 and 13 in Stream Relay Controller 22b) Clients 300a and 300
The packets 12 and 13 sent from the b
e, 400f, the stream relay control device 200
Arrive at b.

The stream relay control device 200b analyzes the packets 12 and 13, recognizes that the packet is a response packet to the packet 10 sent by the stream relay control device 200b, and recognizes the clients 300a and 300b. Recognize that both have connectivity.

Next, the connection status and distribution quality status of each client are stored in the statistical information table 209a of the information storage unit 209 via the control packet analysis unit 203.

FIG. 7 is a diagram showing an example of the structure of the statistical information table 209a according to the second embodiment of the present invention.
This figure is a specific example of the statistical information table 209a that manages what content is received at what quality (here, the discard rate) for each client managed by the client number. In this example, the client with the client number “300a” is the content number “Cont.
The content of "ent A" is received at a discard rate of 0.01, the content of content number "Content B" is received at a discard rate of 0, and the client number is "300b".
Client receives the content with the content number “Content A” at a discard rate of 0.

Then, in response to the statistical information collection / management request from the stream management server 600, the management server response generation unit 210 generates a response packet based on the statistical information table 209a stored in the information storage unit 209. Then, the response packet is stored in the packet buffer 214 of the common memory 212 via the packet rewrite processing unit 207 and sent to the stream management server 600.

According to the second embodiment described above,
After efficiently performing large-scale stream distribution, use the statistical information of the stream reception status from the client,
The stream management server 600 can perform statistical processing / status management.

In the above description of the first and second embodiments, the case where the discard rate is collected as the information of the stream reception status from the client has been described, but not limited to the discard rate, the number of received packets and the fluctuation of the packet. It goes without saying that information such as the above may be collected.

Each process for realizing the above-described stream relay control method according to the present invention is converted into a program code, recorded on a computer-readable recording medium such as a CD-ROM, FD, HD or the like, and distributed to the market. As a result, the stream relay control method of the present invention can be widely spread.

[0070]

According to the present invention, a stream relay control device and a stream relay control system capable of efficiently collecting a large-scale stream and collecting the distribution status of each client and quality control. A stream relay control method can be provided, and the present invention can be widely spread by distributing a recording medium recording the stream relay control method in the market.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a stream distribution network service system according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a main functional block configuration of a stream relay control device according to the first embodiment of the present invention.

FIG. 3 is a sequence diagram showing a processing flow of a stream control protocol packet.

FIG. 4 is a diagram showing an example of contents of a stream control protocol packet according to the present description.

FIG. 5 is a diagram showing a configuration example of a stream distribution network service system according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a main functional block configuration of a stream relay control device according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a configuration example of a statistical information table according to the second embodiment of the present invention.

FIG. 8 is a diagram showing a configuration example of a conventional stream distribution network.

FIG. 9 is a diagram showing a sequence example of a stream control protocol exchanged between a stream server and a client in FIG.

[Explanation of symbols]

10: packet, 11, 12, 13: response packet, 100: stream server, 200 (200a, 200b, 200c): stream relay control device, 201 (201a, 201b): line termination unit, 202: packet distribution unit, 203: control packet analysis unit, 204: stream packet analysis unit, 205: route selection unit, 206: response packet generation unit, 207: packet rewriting processing unit, 208: read control unit, 209: information storage unit, 209a: statistical information Table, 210: Management server response generation unit, 211: Write processing unit, 212: Common memory, 213: Read processing unit, 214: Packet buffer, 300 (300a, 300b, 300c, 300d):
Client, 400 (400a, 400b, 400c, 400d, 4
00e, 400f, 400g, 400h, 400i, 4
00j, 400k): connection line, 401, 402, 403: line, 500 (500a, 500b, 500c, 500d):
Transfer device, 600: Stream management server, SCP: Stream control protocol processing unit, a, b, c, d: Message.

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kiyoshi Yanagimoto 2-3-1, Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (56) Reference JP-A-61-210745 (JP, A) JP 2001-306436 (JP, A) JP 2001-230774 (JP, A) JP 9-172443 (JP, A) JP 8-167894 (JP, A) JP 10-308937 (JP, A) ) JP-A-10-303961 (JP, A) JP-A-7-200505 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 12/56 260

Claims (10)

(57) [Claims] 1. A stream relay control device in a stream distribution network, comprising means for receiving a packet sent from a stream server, and means for analyzing header information of the packet to identify a stream control protocol. , Means for transferring the packet to one or more delivery destinations, means for notifying the packet information when the packet is a stream control protocol, and status information and / or identifier of the stream server from the packet information. A stream relay control device comprising: a means for acquiring and a means for creating a response packet to the packet and transferring the response packet to a stream server. 2. The stream relay control device according to claim 1, wherein in the packet information transmitted from the stream server, a unit that rewrites server information and / or an identifier, and the packet is sent to one or more delivery destinations. A stream relay control device comprising means for transferring. 3. A stream relay control device in a stream distribution network, comprising means for receiving a packet sent from a client or a device having a client function, and analyzing the header information of the packet to obtain a stream. A stream relay device comprising means for identifying a control protocol and means for acquiring the packet information. 4. The stream relay control device according to claim 3, wherein the stream control packet information sent from the client or a device having a client function is accumulated, and a device that responds to a request from a stream management server. A stream relay device comprising: 5. A stream relay control system comprising the stream relay control device according to claim 1 and the stream relay control device according to claim 3. 6. A stream relay control system, comprising: the stream relay control device according to claim 2; the stream relay control device according to claim 4; and a stream management server. 7. A stream relay control method in a stream distribution network, comprising: receiving a packet sent from a stream server; analyzing the packet information to identify a stream control protocol; Transferring the packet to one or more delivery destinations, and then notifying the stream control protocol processing unit of the packet information, obtaining the status information and / or the identifier of the stream server from the packet information, A stream relay control method comprising the step of creating a response packet for a packet and transferring the packet to a stream server. 8. The stream relay control method according to claim 7, wherein the server status information and / or the identifier of the packet information sent from the stream server is rewritten, and the packet is transferred to one or more delivery destinations. And a stream relay control method. 9. A stream relay control method in a stream distribution network, comprising a step of receiving a packet sent from a client or a device having a client function, analyzing the packet information, and using a stream control protocol. And a step of acquiring the packet information, a stream relay control method. 10. A computer-readable recording medium in which the processing steps for realizing the stream relay control method according to any one of claims 7 to 9 are recorded as a program code.