Support of micro-mobility in MPLS-based wireless access networks

Multi-protocol label switching (MPLS) has begun to deploy in the Internet backbone to support service differentiation and traffic engineering. In recent years, there has also been an interest to extend the MPLS capability to the wireless access networks. In this paper, we provide an overview of the MPLS-based micro-mobility management including label switching path setup, packet forwarding, handoff processing, and paging. In order to prevent packet loss during handoff, we propose a medium access protocol (MAC) layer assisted packet recovery scheme. A MAC buffer in the old base station caches the packets dropped by MAC layer and forwards these packets to the new base station. Simulation results show that our proposed scheme can eliminate the packet loss due to handoff and improve the TCP throughput dramatically when compared with IP micro-mobility protocols including cellular IP, HAWAII, and hierarchical mobile IP.