Packet Header Conversion Scheme for VC Merger of MPLS System based on ATM

摘要

PURPOSE: A method for processing packets in the VC(Virtual Channel) merging controller of an ATM-based MPLS(Multi-Protocol Label Switching) system is provided to support the efficiency and scalability of channel resources by executing a packet header conversion function for VC merging while maintaining the original functions of an ATM exchange. CONSTITUTION: If a packet is received from a receiving SAR(Segmentation And Reassembly) element through a UTOPIA interface part(200), a VC merging controller reads values from a merging table by using the channel handle value of the received packet as the offset value of the merging table(202). The VC merging controller assumes the type of each packet, determines a TCID(Transmit Channel IDentifier), a PID(Port Identifier), a VPI(Virtual Path Identifier), and a VCI(Virtual Channel Identifier) from the fields of the merging table, and stores them(202). The VC merging controller confirms whether the received packet is an EFC(Extended Forwarding Control) packet for the message control between an MSC(MPLS Service Controller) and a forwarding engine or between the MSC and a router(203). In case that the received packet is an EFC packet, the VC merging controller reads a TCID recorded in the payload portion of the received packet and inserts it into the channel ID field of a transmitting packet(208).