Connection admission control for capacity-varying networks with stochastic capacity change times

Many connection-oriented networks, such as low Earth orbit satellite (LEOS) systems and networks providing multipriority service using advance reservations, have capacities which vary over time. Connection admission control (CAC) policies which only use current capacity information may lead to intolerable dropping of admitted connections whenever network capacity decreases. We present the admission limit curve (ALC) for capacity-varying networks with random capacity change times. We prove the ALC is a constraint limiting the conditions under which any connection-stateless CAC policy may admit connections and still meet dropping guarantees on an individual connection basis. The ALC also leads to a lower bound on the blocking performance achievable by any connection-stateless CAC policy which provides dropping guarantees to individual connections. In addition, we describe a CAC policy for stochastic capacity change times which uses knowledge about future capacity changes to provide dropping guarantees on an individual connection basis and which achieves blocking performance close to the lower bound