Method to enable routing protocol communication and transit packet forwarding between virtual routers

摘要

Virtual routers 21, 22 within a single physical router 20 share a centralized data plane 25 containing a centralized switch fabric 26 and a plurality of physical network interfaces 211-213, 221-223, each assigned to only one virtual router 21, 22. Using a logical cut-through device CTO between a pair of virtual routers designated respectively client 21 and server 22, packet forwarding information 24 from the server 22 is imported 307 into the client 21, which creates, allocates, and maintains a data structure 23 for the imported information 24, which then resides on the client interfaces 211-213. This imported forwarding information 23 is then integrated into a single forwarding table 23 that is used to recognize an incoming packet at the client 21 and forward it appropriately out through a server interface 221-223 with a single packet forwarding decision in a single transit through the switch fabric 26. Within a physical router 20, a client virtual router 21, 22 can communicate with multiple servers 22 and can concurrently function as a server 22 to multiple clients 21.