PERFORMANCE EVALUATION OF CONNECTION REROUTING SCHEMES FOR ATM-BASED WIRELESS NETWORKS

Supporting mobility in asynchronous transfer mode (ATM)-based broad-ba nd networks with wireless access links poses many technical challenges , One of the most important of these challenges is the need to reroute ongoing connections to/from mobile users as these users move among ba se stations. Connection rerouting schemes must exhibit low handoff lat ency, maintain efficient routes, and limit disruption to continuous me dia traffic while minimizing reroute updates to the network switches, In this paper we propose, describe an implementation for, and experime ntally evaluate the performance of five different connection rerouting schemes. We show that one of these schemes, which operates in two pha ses, executes very fast reroutes (with a measured latency of 6.5 ms) i n a real-time phase and, if necessary, reroutes again in a nonreal-tim e phase to maintain efficient routing, The scheme also results in negl igible disruption to bath audio (e.g., a 1-in-100 chance of a single p acket loss at CD-quality audio rates of 128 kb/s) and low-bit-rate vid eo (e.g.,, a 2-in-100 chance of a single packet loss for 1-Mb/s video) traffic during connection rerouting. Based on these results, we concl ude that simple handoff schemes coupled with a connection management a rchitecture are sufficient for supporting low-bit-rate continuous medi a applications over ATM-based wireless networks.