Method, system and router for changing application in BGP session

1. A method for changing an application in a BGP (Border Gateway Protocol) session, said session being established between a first router and a second router, and an application being enabled in said session, the method comprising:

when changing an application, the first router changing a local capability value stored on a memory of the first router to a value which supports the changed application and changing an address family to correspond with the changed application, wherein changing the application comprises adding a new application, and wherein the method further comprises:

without terminating the BGP session, the first router sending route information corresponding to the changed application to the second router and at the same time sending a Refresh message to the second router, wherein the Refresh message requests the second router to send route information of a designated address for the changed application, and wherein, in response to receiving the route information corresponding to the changed application and the Refresh message, the second router changes a local capability value of the second router as supporting the changed application to enable the changed application without terminating the BGP session.

2. The method of claim 1 , further comprising:

the first router receiving a Refresh message from the second router; and the first router resending route information of a designated address to the second router corresponding to the changed application.

3. The method of claim 1 , further comprising:

the first router disconnecting the established session when receiving a notification message corresponding to the established session.

4. The method of claim 1 , wherein the application comprises at least one of a multicast application, a unicast application, an IPv6 application and an IPv4 application.

5. The method of claim 1 , wherein the application is enabled for the session, and the method comprises changing the application enabled for the session without disconnecting the session.

6. A system for changing an application in a BGP (Border Gateway Protocol) session which has been established between a first router and a second router, the system comprising the first router comprising a processor and a memory storing machine readable instructions executable by the processor when changing an application to change a local capability value to support the changed application and to change an address family to correspond with the changed application, wherein, when executed, the machine readable instructions cause the processor to send route information corresponding to the changed application to the second router, and at the same time send a Refresh message to the second router, wherein the Refresh message is configured to request the second router to resend route information of a designated address for the changed application, and wherein, in response to receiving the route information corresponding to the changed application and the Refresh message, the second router is to change a local capability value of the second router as supporting the changed application to enable the changed application without terminating the BGP session.

7. The system of claim 6 , wherein machine readable instructions stored on a memory of the second router comprise instructions to send a Refresh message to the first router when sending the route information corresponding to the changed application to the first router, the Refresh message being configured to request the first router to resend router information corresponding to a designated address.

8. The system of claim 6 , wherein the first router is further configured to disconnect the established session when receiving a notification message corresponding to the established session.

9. The system of claim 6 , wherein the application comprises at least one of a multicast application, a unicast application, an IPv6 application and an IPv4 application.

10. The system of claim 6 , wherein the application is enabled for the session, and the machine readable instructions executed by the processor change the application enabled for the session without disconnecting the session.

11. The system of claim 10 , wherein the machine readable instructions executed by the processor to change the application are to:

enable a new application to the session without terminating an existing application for the session, and the changed local capability value represents both enabled applications, and the changed address family includes address families for both enabled applications.

12. A router for changing an application in a BGP (Border Gateway Protocol) session, comprising a processor and a storage medium storing machine readable instructions which are executable by the processor when changing an application in the session to change a local capability value stored on a memory of the router to a value which supports the changed application and change an address family to correspond with the changed application, wherein the machine readable instructions, when executed, further cause the processor to send route information corresponding to the changed application to a second router and at the same time send a Refresh message to the second router, wherein the Refresh message is to request the second router to resend route information of a designated address for the changed application, and wherein, in response to receiving the route information corresponding to the changed application and the Refresh message, the second router is to change a local capability value of the second router as supporting the changed application to enable the changed application without terminating the BGP session.

13. The router of claim 12 , wherein the machine readable instructions comprise instructions to disconnect the established session after receiving a notification message corresponding to the established session.

14. The router of claim 12 , wherein the application comprises at least one of a multicast application, a unicast application, an IPv6 application and an IPv4 application.

15. The router of claim 12 , wherein the application is enabled for the session, and the machine readable instructions executed by the processor change the application enabled for the session without disconnecting the session.

16. The router of claim 12 , wherein the machine readable instructions executed by the processor to change the application are to:

enable a new application to the session without terminating an existing application for the session, and the changed local capability value represents both enabled applications, and the changed address family includes address families for both enabled applications.

17. The router of claim 12 , wherein the machine readable instructions executed by the processor to change the application are to:

enable a new application to the session and terminate an existing application for the session, and the changed local capability value represents the new application, and the changed address family is for the new application.