US Patent 7817633 Method of providing virtual router functionality through abstracted virtual identifiers

A method of providing virtual router functionality to a packet responsive to one or more abstracted virtual packet identifiers is provided. The method occurs in a networking device having a router core. The one or more abstracted virtual identifiers are abstracted from one or more virtual identifiers derived from the packet, thus insulating the router core from changes in the one or more virtual identifiers. A packet is received having a VLAN field, and a key is formed from the VLAN field and at least one other packet field. The key is mapped into an abstracted virtual identifier using an indirection mapping process. One or more core virtual router functions are then performed responsive to the abstracted virtual identifier.