Scalable distributed user plane partitioned two-stage forwarding information base lookup for subscriber internet protocol host routes

摘要

Communication sessions are each homed on one of a plurality of line cards in a network element. Packets received by the network element are processed on the home card before being transmitted to a subscriber device, such as a mobile phone or laptop computer. When a packet is received by the network element, it is not necessarily received by the line card that serves as a home card for the respective session. The packet is switched within the network element from the receiving line card, i.e., the trunk card, to the home card. The network element identifies the home card by performing a lookup in a table duplicated on all the line cards using the least significant bits of the IP address in the packet. Using these bits to organize the table limits the size of the table and balances load among the line cards.