Performance Evaluation of the Preemptive Bandwidth Allocation Protocol

We present the Preemptive Bandwidth Allocation Protocol; a distributed QoS-aware signaling protocol that adapts the users’ bandwidth requirement to the limited resources of the network by preempting bandwidth of less prioritized streams. We assume that a connection will have different streams with predefined quality requirements and each stream will have a priority level assigned to it. When a new connection request comes to the network and there is a lack of bandwidth, the communication service will try to preempt some streams of existing connections to satisfy the new requests without disconnecting the basic stream of any of these existing connections. The aim is to accommodate the maximum number of users within the network with at least their minimum requirements (e.g. I frames in a MPEG-2 media data). We also present a performance evaluation that compares this distributed preemptive approach with a centralized version and the traditional non-preemptive approach.