Patent ID: 7756998

Claim:
A method of managing virtual routing forwarding (VRF) tables at a provider edge (PE) router of a L3 virtual private network (VPN), said PE router maintaining a VPN-IP master routing information base (RIB) and a sub-RIB for each said VRF table, comprising: maintaining an import route target (ImpRT) tree comprising all ImpRT attributes currently configured on said PE router; modifying an ImpRT attribute of a first VRF table in said PE router; searching said ImpRT tree for a match to said modified ImpRT attribute to identify a second VRF table in said PE router having a matching ImpRT attribute; for peers supporting a route refresh feature, performing a route refresh operation only when said match is not found; for peers that do not support the route refresh feature, maintaining rejected routes in a rejected routes tree; searching for routes in a sub-RIB associated with said second VRF table; and copying said routes from said sub-RIB into said first VRF table based on all route target attributes configured for said first VRF table, including said modified ImpRT attribute.