(A) study on the bandwidth management algorithm for LAN/MAN interconnection via ATM network

Abstract

The interconnection of distinct LAN/MAN is one of the most challenging services that broadband integrated services digital network(B-ISDN) have to provide. Some problems in interconnecting LAN/MAN over the ATM network are the support of connectionless traffic and the selection of proper congestion control for LAN traffic. In this paper, we propose a time-dependent dynamic bandwidth management(TDBM) algorithm that allocates the bandwidth by checking a threshold and using timers. If the queue exceeds the threshold, the source node starts to renegotiate the bandwidth by sending a bandwidth increment request(BIR) message. If the node receives a ``Accept`` message after sending BIR, it increases its bandwidth by a fixed amount. Whenever the destination node receives BIR message or its timer expires, it sends a ``Accept`` message and resets its timer if the available bandwidth remains. However, if the buffer in the source node is empty for a fixed duration, it releases the bandwidth by sending a bandwidth release(BR) message to the destination node. We estimate the performance of the TDBM algorithm by utilizing an approximate analytical model and compare it with that of the variable bandwidth connection(VBC) algorithm by computer simulations. The proposed algorithm can effectively utilize the available bandwidth and lower the packet loss in ATM networks.