JP5136492B2 - Communication service providing method, network control device and program - Google Patents

Description

  The present invention relates to a technique for providing a communication service in which service quality is guaranteed between communication terminals connected to different management domains.

  The Internet is obtained by interconnecting a plurality of networks having different management entities, and a network managed by a certain management entity is called a management domain. For example, providing a communication service that guarantees a predetermined quality of service between two terminals connected to a certain management domain can be performed by the management domain independently, but it is connected to a different management domain 2. In order to provide a communication service that guarantees a predetermined service quality between two terminals, control across management domains is required.

  For this reason, Patent Document 1 is provided with a multi-domain service broker that mediates between network service management devices that manage each domain, thereby ensuring a predetermined service quality between terminals in different management domains. The structure which provides is disclosed. However, the management domain through which the communication service is provided is first determined by the multi-domain service broker and then negotiated between each network service management device group, and it takes time to start providing the service. There's a problem.

  On the other hand, in Patent Document 2, a QoS server is provided in each management domain, and a terminal requesting a communication service makes a request for the communication service to the QoS server in the connected management domain, and requests the communication service. The received QoS server determines an adjacent management domain to be used for providing the communication service based on the address of the destination terminal, transmits a resource request message to the QoS server of the determined adjacent management domain, and receives the resource request message A configuration is disclosed in which a QoS server repeats similar processing to provide a communication service that guarantees a predetermined service quality between terminals in different management domains.

JP 2001-282760 A JP 2007-221352 A

  In the configuration described in Patent Document 2, each QoS server adds the IP address on the self management domain side of the interconnection point with the adjacent management domain to the resource request message transmitted to the QoS server of the adjacent management domain, The QoS server in the adjacent management domain recognizes the position that is the starting point in its own management domain from this IP address. However, for example, when the management domains are connected by a plurality of layer 2 links, even if the IP address of the interconnection point is specified, it is not possible to specify which layer 2 link is used, thus guaranteeing service quality. There is a problem that you can not. In addition, the configuration described in Patent Document 2 has a problem in that if service quality cannot be ensured in a certain management domain, the service cannot be provided even if another route is available.

  Accordingly, an object of the present invention is to provide a communication service providing method, a network control apparatus, and a program that solve the above-described problems.

According to the control device of the present invention,
A control device that controls one network among communication systems in which a plurality of networks are interconnected, and a network that can be used to provide a communication service to a terminal connected to another network; and A service request message having a destination / transfer destination correspondence table indicating a gateway identifier for identifying an interface of a device at an interconnection point with a network that can be routed, and including an address of a destination terminal of the communication service, a quality of service, and a gateway identifier Alternatively, when a service request message including the address of the destination terminal of the communication service, the quality of service, and the address of the communication terminal requesting the communication service is received, the network is controlled by the destination terminal based on the address of the destination terminal. Determine whether it is a connected terminal When the destination terminal is not connected to the network to be controlled, select one interconnection point with the network that can be routed based on the destination / transfer destination correspondence table, and correspond to the gateway identifier included in the received service request message A communication service satisfying the service quality from the connection point with the communication terminal requesting the communication service determined from the address of the communication terminal requesting the interconnection point or communication service to the selected interconnection point; If it can be provided, a service request message including the address of the destination terminal, the quality of service and the gateway identifier of the selected interconnection point is connected to the selected interconnection point. It transmits to the control apparatus of the network which is a tip.

According to another embodiment of the control device in the present invention,
If a communication service satisfying the service quality cannot be provided up to the selected interconnection point, one other interconnection point is selected based on the destination / transfer destination correspondence table, and the selected other interconnection point is selected. Until it is determined whether or not a communication service satisfying the service quality can be provided, and if it can be provided, a service including the address of the destination terminal, the service quality, and a gateway identifier of the selected other interconnection point It is also preferable to send a request message to the network control device to which the selected other interconnection point is connected.

According to another embodiment of the control device in the present invention,
Provide a service to the device that is the source of the received service request message when it is not possible to provide a communication service that satisfies the quality of service for all the connection points with the network that can be routed shown in the destination / transfer destination correspondence table. It is also preferable to send a negative response message indicating that the request cannot be made.

Furthermore, according to another embodiment of the control device of the present invention,
When a negative response message is received for a service request message transmitted to another control device, based on the destination / forwarding destination correspondence table, an interconnection point corresponding to the gateway identifier included in the transmitted service request message It is also preferable to determine whether or not a communication service satisfying the service quality can be provided up to an interconnection point other than.

According to the program of the present invention,
A computer functions as the control device.

According to the communication service providing method of the present invention,
A plurality of networks are interconnected, and each network is provided with a control device that controls devices in the network, and each control device provides a communication service to terminals connected to other networks In a communication system having a destination / transfer destination correspondence table indicating a network that can be routed for communication and a gateway identifier that identifies an interface of a device at an interconnection point of the network that can be routed, the first network Between the first terminal connected to the second terminal and the second terminal connected to the second network, providing a communication service that satisfies the service quality required by the first terminal, the first terminal comprising: The first control device of the first network includes a second terminal address, a requested quality of service, and a first terminal address. Transmitting a service request message, the first control device determining a second network to which the second terminal is connected based on the address of the second terminal, and the first control device comprising: Selecting one interconnection point from interconnection points with a network that can be routed to provide a communication service to a terminal connected to the second network based on the destination / transfer destination correspondence table; A step of determining whether or not the one control device can provide a communication service satisfying the service quality from the interconnection point with the first terminal to the interconnection point with the selected network; Includes a service request message including an address of the second terminal, the quality of service, and a gateway identifier of an interconnection point with the selected network. Characterized in that it comprises a step of transmitting to the controller of the serial, which is the connection destination of the selected interconnection point network.

  Provides communication services satisfying a predetermined service quality between two terminals connected to different management domains without providing an intermediary device between control devices that control each management domain, and regardless of the interconnection mode can do. Furthermore, even when a communication service satisfying a predetermined service quality cannot be provided in a certain management domain, the communication service can be provided by searching for another route.

1 is a system configuration diagram of a communication system for explaining a communication service providing method according to the present invention. FIG. 2 is a diagram showing an example of a destination / transfer destination correspondence table held by a control device A in the configuration of FIG. 1. FIG. 2 is a diagram showing an example of a destination / transfer destination correspondence table held by a control apparatus B in the configuration of FIG. 1. It is a 1st sequence diagram of a communication service provision method. It is a 2nd sequence diagram of the communication service provision method. It is a 3rd sequence diagram of a communication service provision method.

  EMBODIMENT OF THE INVENTION The form for implementing this invention is demonstrated in detail below using drawing. In providing a communication service across multiple management domains or networks, the network to which the terminal that requested the service is connected is the upstream side, and the network to which the terminal that is the communication partner of the terminal that requested the service is connected. Downstream. For example, when the terminal X connected to the network K requests communication with the terminal Y connected to the network M and provides a communication service via the network L connected to both the networks K and M, the network K is upstream of networks L and M, network L is downstream of network K and upstream of network M, and network M is referred to as downstream of networks K and L.

  FIG. 1 is a system configuration diagram of a communication system for explaining a communication service providing method according to the present invention. According to FIG. 1, the communication system comprises control devices A, B, C and D according to the invention, networks A, B, C and D and terminals S and T. In FIG. 1, network A is connected to network B at one location, and the gateway identifier on the network A side at the interconnection point is A1, and the gateway identifier on the network B side is B1. The network A is connected to the network C at two locations, the gateway identifier on the network A side at one interconnection point is A2, the gateway identifier on the network C side is C1, and the network A side at the other interconnection point The gateway identifier is A3, and the gateway identifier on the network C side is C4.

  The network B is connected to the networks C and D in addition to the network A. The gateway identifier on the network B side at the interconnection point between the network B and the network C is B2, the gateway identifier on the network C side is C2, and the network B The gateway identifier on the network B side at the interconnection point between the network D and the network D is B3, and the gateway identifier on the network D side is D1. Further, the network C is connected to the network D in addition to the networks A and B, the gateway identifier on the network C side at the interconnection point between the network C and the network D is C3, and the gateway identifier on the network D side is D2. The gateway identifier is a value indicating the physical interface position of the device at the interconnection point.

  Each of the networks A, B, C, and D is a management domain, and the control device A has a function of making settings necessary for providing communication services for various communication devices in the network A. Similarly, the control device B is a control device for the network B, the control device C is a control device for the network C, and the control device D is a control device for the network D. Each control device is configured to be able to communicate with a control device in another domain.

  The control apparatus according to the present invention includes a destination / transfer destination correspondence table. 2 is an example of a destination / transfer destination correspondence table held by the control device A in the configuration of FIG. 1, and FIG. 3 is a destination / transfer destination correspondence table held by the control device B in the configuration of FIG. It is an example of a table. 2 and 3, the destination NW is a network to which a terminal serving as a destination of the communication service is connected, and the transfer destination NW is a communication terminal connected to the corresponding destination NW. The local GW is a gateway identifier on the network side that is managed by the own device at the point of interconnection with the network that can be routed. The remote GW is a gateway identifier on the network side that can be routed at the interconnection point with the network that can be routed, and the priority is when there are a plurality of networks and interconnection points that can be routed to one destination NW. The selection order is shown. In the present embodiment, it is assumed that the values are selected in ascending order.

  For example, according to FIG. 2, when the terminal serving as the destination of the communication service is a terminal connected to the network D, the network A has an interface corresponding to the route passing through the network B and the gateway identifier C1 of the network C. Can be used, and the route passing through the interface corresponding to the gateway identifier C4 of the network C has a priority of 10, and corresponds to the gateway identifier C1 of the network C. Since the priority of the route passing through the interface is 20, and the priority of the route passing through the interface corresponding to the gateway identifier C4 of the network C is 50, it is indicated that the route passing through the network B is given priority. ing.

  Similarly, according to FIG. 3, the network B can use three routes for providing communication services to terminals connected to the network D, and the priority is a route that passes through the network D. Is the highest, followed by the route through network C, and finally the route through network A. Hereinafter, processing when the terminal S connected to the network A shown in FIG. 1 starts communication with the terminal T connected to the network D will be described with reference to FIG. In the following description, a band is used as a service quality parameter. However, other parameters such as a delay can be used, or a combination of a plurality of parameters can be used.

  First, the terminal S transmits a service request message for requesting a communication service with the terminal T to the control device A. The service request message transmitted by the terminal S includes the IP address of the terminal S, the requested quality of service, in this example, the requested bandwidth, and the IP address of the terminal T as the destination address. From the address, the network to which the terminal T as the destination is connected, the network D in this example, is determined, and the route determination process is performed using the destination / transfer destination correspondence table shown in FIG. In the route determination process, first, the control device A determines whether or not a route having a high priority through the network B among the three routes to the network D can be used. Specifically, from the connection point with the terminal S in the network A, determined from the IP address of the terminal S, to the gateway identifier B1 via the interface corresponding to the gateway identifier A1 that is the connection point with the network B. It is determined whether or not communication resources for providing a communication service that satisfies the requested service quality can be secured in the section leading to the corresponding interface, that is, whether or not the requested bandwidth can be secured in this example. When the route can be secured, the route via the network B is selected. When the route cannot be secured, it is determined whether or not the route via the interface corresponding to the gateway identifier C1 of the network C can be used. If it can be used, the route via the interface corresponding to the gateway identifier C1 of the network C is selected. If it cannot be used, whether or not the route via the interface corresponding to the gateway identifier C4 of the network C can be used. Determine. If it can be used, a route via the interface corresponding to the gateway identifier C4 of the network C is selected, and if it cannot be used, a negative response message indicating that the connection cannot be made is transmitted to the terminal S. In this example, it is assumed that a route via the network B is available (S41).

  In this case, the control device A transmits a service request message to the control device B which is a control device of the network B which is one downstream. This service request message includes the IP address of the terminal T that is the destination address, the gateway identifier B1 that is the starting point of the communication service in the network B, and the requested bandwidth requested by the terminal S. The control device B performs the route determination process using the destination / transfer destination correspondence table shown in FIG. In this example, it is assumed that the route having the highest priority via the network D can be used (S42).

  Therefore, the control device B transmits to the control device D, which is a control device of the network D that is one downstream, the IP address of the terminal T that is the destination address, the gateway identifier D1 that is the starting point of the communication service in the network D, A service request message including the requested bandwidth requested by the terminal S is transmitted. The control device D recognizes from the IP address of the terminal T that the terminal T is connected to the network D, determines its connection point, and connects the interface corresponding to the gateway identifier D1 and the terminal T. It is determined whether or not the required bandwidth can be secured between the points. In this example, it can be secured (S43).

  In this case, the control device D makes a setting necessary for service provision to each communication device in the network D, can provide the service to the control device B, and indicates that the setting has been completed. Similarly, the control apparatus B performs setting necessary for providing the service to each communication apparatus in the network B, can provide the service to the control apparatus A, and the setting is performed. An acknowledgment message indicating completion is transmitted, and finally, the control device A can make settings necessary for service provision to each communication device in the network A and can provide the service to the terminal S. And the acknowledgment message which shows that the setting was completed is transmitted (S44). Through the above processing, it is possible to provide a communication service that guarantees service quality between the terminal S and the terminal T connected to different management domains.

  For example, when the transmission delay from terminal S to T is included as the service quality, terminal S includes the maximum allowable delay value in the service request message, and each control device is within the network managed by itself. If the delay is less than or equal to the delay included in the service request message, it is determined that the service can be provided, and a value obtained by subtracting the delay in the network managed by itself from the delay included in the received service request message. And set in the service request message to be transmitted to the downstream control device. Each control device determines that the service cannot be provided when the delay in the network managed by the control device is larger than the delay included in the service request message, and transmits a negative response message to the control device one upstream. To do.

  Next, a process when the requested bandwidth cannot be secured between the interface corresponding to the gateway identifier D1 and the connection point of the terminal T in S43 will be described with reference to FIG. In this case, the control device D transmits a negative response message indicating that the service cannot be provided to the control device B one upstream. Receiving the negative response message, the control device B again performs route determination processing using the destination / forwarding destination correspondence table shown in FIG. However, in this case, it is determined whether or not a route having a lower priority than the target route of the negative response message can be used. Therefore, in this example, first, it is determined whether or not the route having the second highest priority and passing through the network C is available. Here, it is assumed that the route to the network C is available (S51). When the route to the network C is not available, the network with the next highest priority is the network A, but the network A is a network on the upstream side of the service request message. Since there is no other path in this case, the control device B transmits a negative response message to the control device A that is one upstream.

  The control device C that has received the service request message from the control device B performs route determination processing using a destination / transfer destination correspondence table (not shown). In this example, in the network C, a required bandwidth can be secured in a route from the interface corresponding to the gateway identifier C2 to the interface corresponding to the gateway identifier D2 via the interface corresponding to the gateway identifier C3. (S52).

  Therefore, the control device C transmits to the control device D a service request message including the IP address of the terminal T, the gateway identifier D2 that is the starting point of the communication service in the network D, and the requested bandwidth requested by the terminal S. The control device D recognizes from the IP address of the terminal T that the terminal T is connected to the network D, determines its connection point, and connects the interface corresponding to the gateway identifier D2 and the terminal T. It is determined whether or not the required bandwidth can be secured between the points. In this example, it can be secured (S53). Therefore, as in the process of S44, the acknowledgment message is sequentially transferred to the control device located upstream, the setting is performed for the communication device in each network, and the service provision is started (S54).

  In the above-described embodiment, the control device that has received the negative response message determines whether or not the other route can be used. When a service request message is transmitted and all routes are not available, a negative response message is transmitted to the control device one upstream. However, when a negative response message is received, it is simply transferred to the upstream control device, and the network control device that accommodates the terminal that has made the service start request again serves the other route. A form in which a request message is transmitted may be used. FIG. 6 is a sequence diagram in this case. As in FIG. 5, in S43, the processing when the requested bandwidth cannot be secured between the interface corresponding to the gateway identifier D1 and the connection point of the terminal T is shown.

  The control device D transmits a negative response message indicating that service cannot be provided to the upstream control device B, and the control device B transmits a negative response message to the upstream control device A. Receiving the negative response message, the control device A again performs route determination processing using the destination / transfer destination correspondence table shown in FIG. In this example, it is assumed that a route that passes through the interface corresponding to the gateway identifier C1 of the network C having the second highest priority is available (S61). The control device C that has received the service request message from the control device A performs route determination processing using a destination / transfer destination correspondence table (not shown). In this example, it is assumed that the required bandwidth can be secured up to the route to the network D in the network C (S62). Therefore, the control device C transmits to the control device D a service request message including the IP address of the terminal T, the gateway identifier D2 that is the starting point of the communication service in the network D, and the requested bandwidth requested by the terminal S. The control device D recognizes from the IP address of the terminal T that the terminal T is connected to the network D, determines its connection point, and connects the interface corresponding to the gateway identifier D2 and the terminal T. It is determined whether or not the required bandwidth can be secured between the points. In this example, it can be secured (S63). Therefore, as in the process of S44, the acknowledgment message is sequentially transferred to the control device located upstream, the setting is performed for the communication device in each network, and the service provision is started (S64).

  Through the above processing, it is possible to provide a communication service by selecting a route that can ensure service quality from a plurality of routes across a plurality of management domains without providing a device that mediates between control devices of each management domain. It becomes possible. Each control device has a destination / forwarding destination correspondence table that includes a destination network, a transit network, and a gateway identifier that identifies the interfaces of the devices at both ends at the interconnection point of the transit network. In this way, each control device performs route determination processing, and includes a gateway identifier that is a starting point of service start in the downstream network in the service request message transmitted to the downstream control device. Thus, it is possible to provide a service that guarantees service quality between terminals connected to different management domains regardless of the interconnection form. Further, when a negative response message is received for the transmitted service request message, the control device determines another available route, and if there is another available route, a service request is sent to this route. Since the message is transmitted, a service can be provided by searching for an available route from a plurality of routes.

  The control device according to the present invention can be realized by a program that causes a computer to function as the control device described above. The computer program is stored in a computer-readable storage medium or can be distributed via a network. Furthermore, the present invention can be realized by a combination of hardware and software.

Claims (6)

A control device that controls one network among communication systems in which a plurality of networks are interconnected,
A local gateway that identifies a network that can be used to provide a communication service to a terminal that is connected to another network, and an interface on the network side that is managed by the device at an interconnection point between the network that can be passed A destination / forwarding destination correspondence table indicating an identifier and a remote gateway identifier that identifies an interface on the network side that can be routed at an interconnection point of the network that can be routed ;
Service request message including address of communication service destination terminal, service quality and remote gateway identifier, or service request message including address of communication service destination terminal, service quality and address of communication terminal requesting communication service , Based on the address of the destination terminal, determine whether the destination terminal is a terminal connected to the network to be controlled,
When the destination terminal is not connected to the network to be controlled, select one interconnection point with the network that can be routed based on the destination / forwarding destination correspondence table, and correspond to the remote gateway identifier included in the received service request message Corresponding to the remote gateway identifier of the selected interconnection point through the interface corresponding to the local gateway identifier of the selected interconnection point from the address of the communication terminal requesting the communication service or the communication terminal It is determined whether or not a communication service that satisfies the service quality can be provided up to the interface ,
If it can be provided, a service request message including the address of the destination terminal, the quality of service and the remote gateway identifier of the selected interconnection point is sent to the control device of the network to which the selected interconnection point is connected. Send,
Control device. If a communication service satisfying the service quality cannot be provided up to the selected interconnection point, one other interconnection point is selected based on the destination / transfer destination correspondence table, and the selected other interconnection point is selected. Until it is determined whether a communication service satisfying the service quality can be provided,
If it is possible to provide a service request message including the address of the destination terminal, the quality of service and the remote gateway identifier of the selected other interconnection point, the network to which the selected other interconnection point is connected To the control device
The control device according to claim 1. When it is not possible to provide a communication service that satisfies the quality of service for all the interconnection points with the network that can be routed shown in the destination / transfer destination correspondence table,
Sending a negative acknowledgment message indicating that the service cannot be provided to the device that sent the received service request message;
The control device according to claim 2. When a negative response message is received for a service request message sent to another control device,
Whether or not a communication service satisfying the service quality can be provided to an interconnection point other than the interconnection point corresponding to the remote gateway identifier included in the transmitted service request message based on the destination / transfer destination correspondence table judge,
The control device according to claim 3.   The program which makes a computer function as a control apparatus of any one of Claim 1 to 4. A plurality of networks are interconnected, and each network is provided with a control device that controls devices in the network, and each control device provides a communication service to terminals connected to other networks A local gateway identifier for specifying a network-side interface managed by the self-device at an interconnection point between the network that can be routed for the network and the network that can be routed, and an interconnection point between the network that can be routed In a communication system that holds a destination / forwarding destination correspondence table indicating a remote gateway identifier that identifies an interface on the network side that can be routed ,
A method for providing a communication service satisfying a quality of service required by a first terminal between a first terminal connected to a first network and a second terminal connected to a second network,
A first terminal sending a service request message including an address of a second terminal, a requested quality of service and an address of the first terminal to the first control device of the first network;
A first controller determining a second network to which the second terminal is connected based on the address of the second terminal;
Based on the destination / forwarding destination correspondence table, the first control device has one interconnection point from an interconnection point with a network that can be routed to provide a communication service to a terminal connected to the second network. A step of selecting
The first control device passes through the interface corresponding to the local gateway identifier of the selected interconnection point from the interconnection point corresponding to the remote gateway identifier included in the received service request message or the address of the first terminal. Determining whether a communication service satisfying the quality of service can be provided up to the interface corresponding to the remote gateway identifier of the selected interconnection point ;
If it can be provided, a service request message including the address of the second terminal, the quality of service and the remote gateway identifier of the interconnection point with the selected network is the connection destination of the selected interconnection point. Transmitting to a network controller;
A method comprising:

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