The Impact of Handover Protocols on the Performance of ABR Flow-Control Algorithms in a Wireless ATM Network

Considering the high-speed data transfer by the ABR service class in a wireless ATM network, we investigate the impact of forward and backward hard handover protocols on the performance of the three rate-based ABR flow-control schemes Explicit Rate Indication for Congestion Avoidance (ERICA+), Fuzzy Explicit Rate Marking (FERM) and a new promising adaptation of FERM, called FERMA. We evaluate the performance of these flow-control protocols by means of an object-oriented simulation model of a basic client-server architecture. Considering a standard hard handover protocol in a wireless ATM network, we show that our proposed enhanced signaling schemes based on a congestion-awareness concept and their integration into the ABR flow control have a positive influence on the stability and efficiency of the cell transfer by ABR connections. Moreover, we point out that the new adaptation of the fuzzy-control scheme FERM provides a promising alternative to the ERICA+ algorithm.