EFFICIENT ONLINE CALL CONTROL ALGORITHMS

In this paper we study the problem of on-line call control in a commun ication network, namely, the problem of accepting or rejecting an inco ming call (a request for a connection between two points in a network) without having the knowledge of future calls. The problem is a part o f the more general problem of bandwidth allocation and management. Int uition suggests that knowledge of future call arrivals can be crucial to the performance of the system. In this paper, however, we present p reemptive deterministic on-line call control algorithms. We use compet itive analysis to measure their performance--i.e., we compare our algo rithms to their off-line, clairvoyant counterparts--and prove optimali ty for some of them. We consider two specific networks, a line of node s and a single edge, and investigate a variety of cases concerning the value of the calls. The value is accrued only if the call terminates successfully; otherwise-if the call is rejected, or prematurely termin ated--no value is gained. The performance of the algorithm is then mea sured by the cumulative value achieved, when given a sequence of calls . The variety of call value criteria that we study--constant; proporti onal to the length of the call's route; proportional to its holding ti me--captures many of the natural cost assignments to network services. (C) 1997 Academic Press.