Routing control system for l3vpn service network

Abstract

A routing control system comprising a system controller and master and slave routing servers, wherein the master routing server includes a plurality of logical controllers, each of which performs routing control for each of the user networks, the system controller monitors a load state of the master routing server and migrates at least one of the plurality of logical controllers from the master routing server to the slave routing server when the load state has satisfied a predetermined condition, so that the slave routing server inherits routing control for a particular user network associated with the migrated logical controller.

1 . A routing control system to be located in an L3VPN service network connected to a plurality of user networks, comprising: a system controller; a master routing server; and a slave routing server,
 wherein said master routing server includes a plurality of logical controllers, each of which is associated with one of said plurality of user networks to perform routing control for the user network,   wherein said system controller monitors a load state of said master routing server and migrates at least one logical controller selected out of said plurality of logical controllers operating on said master routing server from the master routing server to said slave routing server when the load state has satisfied a predetermined condition, so that the slave routing server inherits routing control for a particular user network associated with the migrated logical controller by activating the logical controller.   
   
   
       2 . The routing control system according to  claim 1 ,
 wherein said system controller includes a migration controller which issues migration commands for said selected logical controller to said master routing server and said slave routing server, and   wherein, in response to said migration commands from said migration controller, said master routing server transfers said selected logical controller to said slave routing server and said slave routing server activates the logical controller to inherit routing control for said particular user network.   
   
   
       3 . The routing control system according to  claim 2 ,
 wherein said system controller includes a CPU load monitor which obtains CPU load information from said master routing server to determine whether the CPU load has reached a predefined threshold value, and   wherein, when the CPU load has reached the predefined threshold value, said CPU load monitor selects at least one logical controller out of said plurality of logical controllers operating on said master routing server and issues a migration request for the selected logical controller to said migration controller.   
   
   
       4 . The routing control system according to  claim 2 ,
 wherein said system controller includes a routing control packet monitor which obtains load information including the amount of routing control packets for each of said logical controllers from said master routing server to determine whether there exists a logical controller for which the amount of routing control packets has reached a predefined threshold value, and   wherein, when the amount of routing control packets of any logical controller has reached the predefined threshold value, said routing control packet monitor selects at least one logical controller out of said plurality of logical controllers operating on said master routing server and issues a migration request for the selected logical controller to said migration controller.   
   
   
       5 . The routing control system according to  claim 3 ,
 wherein said migration controller determines whether the migration of said selected logical controller is allowed or not when said migration request was received, and issues migration commands for the logical controller to said master routing server and said slave routing server when the migration of the logical controller was allowed.   
   
   
       6 . The routing control system according to  claim 4 ,
 wherein said migration controller determines whether the migration of said selected logical controller is allowed or not when said migration request was received, and issues migration commands for the logical controller to said master routing server and said slave routing server when the migration of the logical controller was allowed.   
   
   
       7 . The routing control system according to  claim 1 ,
 wherein said master routing server, said slave routing server and said system controller are connected to the same core node in said L3VPN service network, and said migration of logical controller is carried out via the core node or an internal switch for interconnecting the master and slave routing servers.   
   
   
       8 . The routing control system according to  claims 1 ,
 wherein said master routing server and said slave routing server are connected to different core nodes in said L3VPN service network, and said migration of logical controller is carried out via a communication line in the L3VPN service network.   
   
   
       9 . The routing control system according to  claim 8 ,
 wherein said plurality of user networks are connected to the same edge node in the L3VPN service network,   wherein the edge node forwards routing control packets received from each of said user networks, in accordance with a management table indicating the correspondence of identifiers of said user networks and addresses of said master and slave routing servers, and   wherein said system controller issues a command for updating the management table to said edge node when said logical controller has immigrated from said master routing server to said slave routing server.   
   
   
       10 . A routing control system to be located in an L3VPN service network connected to a plurality of user networks, comprising: a system controller; a master routing server; and a slave routing server,
 wherein said master routing server includes a plurality of logical controllers, each of which is associated with one of said plurality of user networks to perform routing control for the user network,   wherein said system controller obtains load information indicating the amount of routing control packets from edge nodes to which said user networks are connected and migrates at least one logical controller selected out of said plurality of logical controllers operating on said master routing server from the master routing server to said slave routing server when the amount of routing control packets has satisfied a predetermined condition, and   wherein said slave routing server inherits routing control for a particular user network associated with the migrated logical controller by activating the logical controller.   
   
   
       11 . The routing control system according to  claim 10 ,
 wherein said system controller includes a migration controller which issues migration commands for said selected logical controller to said master routing server and said slave routing server, and   wherein, in response to the migration commands from the migration controller, said master routing server transfers the selected logical controller to said slave routing server and said slave routing server activates the logical controller to inherit routing control for said particular user network.   
   
   
       12 . The routing control system according to  claim 11 ,
 wherein said system controller includes a user network monitor which obtains load information indicating the amount of routing control packets from said edge nodes to determine whether the amount of routing control packets has reached a predefined threshold value, and   wherein said user network monitor selects at least one logical controller out of said plurality of logical controllers operating on said master routing server and issues a migration request for the selected logical controller to said migration controller when the amount of routing control packets has reached a predefined threshold value.   
   
   
       13 . The routing control system according to  claim 12 ,
 wherein said migration controller determines whether the migration of said selected logical controller is allowed or not when said migration request was received, and issues migration commands for the logical controller to said master routing server and said slave routing server when the migration of the logical controller was allowed.   
   
   
       14 . The routing control system according to  claim 10 ,
 wherein said master routing server, said slave routing server and said system controller are connected to the same core node in said L3VPN service network, and said migration of logical controller is carried out via the core node or an internal switch for interconnecting the master and slave routing servers.   
   
   
       15 . The routing control system according to  claim 10 ,
 wherein said master routing server and said slave routing server are connected to different core nodes in said L3VPN service network, and said migration of logical controller is carried out via a communication line in the L3VPN service network.   
   
   
       16 . The routing control system according to  claim 15 ,
 wherein said plurality of user networks are connected to the same edge node in the L3VPN service network,   wherein the edge node forwards routing control packets received from each of said user networks, in accordance with a management table indicating the correspondence of identifiers of said user networks and addresses of said master and slave routing servers, and   wherein said system controller issues a command for updating the management table to said edge node when said logical controller has immigrated from said master routing server to said slave routing server.