ADAPTIVE BANDWIDTH ESTIMATION AND ALLOCATION FOR DQDB MAN INTERWORKING WITH B-ISDN

The main challenge for internetting LAN/MAN across B-ISDN comes from t he fact that B-ISDN is connection-oriented but LANs and MANs run conne ctionless protocols. The critical issue is for the gateway to estimate the incoming traffic bit rate and negotiate with the B-ISDN for bandw idth allocation. In this paper we propose an adaptive estimation metho d for connectionless DQDB MAN interworking with B-ISDN. Due to the inh erent nature of DQDB, the time window of bandwidth estimation can be a djusted dynamically. This results in a smaller fluctuation of required bandwidth estimation, so the gateway doesn't need to renegotiate freq uently. In addition, based on the knowledge of bandwidth required, we propose a strategy for bandwidth allocation. Performance results are c ompared for the following schemes: adaptive time window, fixed time wi ndow, fixed cell window and a buffer threshold scheme. It shows that t he proposed scheme performs better than other such schemes.