Communication control system, communication control method, routing controller and router suitably used for the same

A routing controller configured to switch a routing path between routers from a first routing path to a second routing path, the routing controller comprising:

• a trigger receiver configured to receive a trigger indicating a need to route via the first router on the second routing path in a case where the first router has a service control function including an accounting function, a monitoring function or a media converting function;
• an address information provision requester configured to send a request to the first router to provide address conversion information in accordance with reception of the trigger;
• an address conversion information creation requester configured to send a request to a second router, which is located on a demarcation point of the first routing path and the second routing path, to create first address conversion information, which associates a destination address of received data with an IP address of the first router, for converting data destined for a destination terminal to data destined for the first router, and to send a request to the first router to create second address conversion information for converting data destined for the first router to data destined for the destination terminal, based on the address conversion information acquired from the first router;
• an address conversion information change requester configured to send a request to the second router to change the first address conversion information;
• and
• an address conversion information deletion requestor configured to request the second router to delete the first address conversion information.

A communication control method for

• switching, by a routing controller, a routing path between routers from a first routing path to a second routing path, wherein a first router is located on the second routing path, and a second router is located on a demarcation point of the first routing path and the second routing path, comprising;
• receiving, at the routing controller, a trigger indicating a need to route via the first router in a case where the first router has a service control function including an accounting function, a monitoring function or a media converting function;
• sending a request, by the routing controller, to the first router to provide address conversion information in accordance with reception of the trigger;
• sending a request, by the routing controller, to the second router to create first address conversion information, which associates a destination address of received data with an IP address of the first router, for converting data destined for a destination terminal to data destined for the first router, and sending a request to the first router to create second address conversion information for converting data destined for the first router to data destined for the destination terminal, based on the address conversion information acquired from the first router;
• providing, from the first router, address conversion information to the routing controller in accordance with the request to provide address conversion information from the routing controller;
• creating and managing, by the first router, the second address conversion information in accordance with the request to create second address conversion information from the routing controller;
• converting, by the first router, a destination address of received data based on the second address conversion information;
• performing, by the first router, a routing processing of the data converted by the first address converter;
• creating and managing, by the second router, the first address conversion information in accordance with the request to create first address conversion information from the routing controller;
• converting, by the second router, a destination address of received data based on the first address conversion information by encapsulating the destination address of the received data with the IP address of the first router;
• performing, by the second router, a routing processing of the data converted by the second address converter using the IP address of the first router;
• and
• requesting, by the routing controller, the second router to delete the first address conversion information.