Procedures for constructing QoS FEC and looking up packets on Emulated Leased Line Services in MPLS LERs

摘要

PURPOSE: A method for configuring QoS(Quality of Service) FEC(Forwarding Equivalence Class) and searching packets to classify and transmit emulated leased line service packets in an MPLS(Multi Protocol Label Switching) edge router is provided to search multiple fields of a packet header by multistage with configuring forwarding data tables and search tables, thereby providing a high-quality emulated leased service through an MPLS network. CONSTITUTION: If a packet is input(41), a destination address, a destination net mask, a source address, and source net mask data are extracted from a header of the packet(42). A search table 1 for an emulated leased line service is searched by using a longest prefix matching method with source net mask as key value to find out a source address identifier(43). A search table 2 for an emulated leased line service is searched by using the longest prefix matching method with the destination address and destination net mask source net mask as key value to find out a destination address identifier(44). A search table 3 for an emulated leased line service is searched by using an exact matching method with the source address identifier and the destination address identifier as key value to find out output label and output interface from a search table 4(45). An MPSL header stating the output label is attached to the packet(46). The packet is transmitted through the output interface(47).