Bandwidth allocation and routing in virtual path based ATM networks

The virtual path (VP) concept in ATM networks simplifies traffic control and resource management. For bandwidth allocation, a VP can carry traffic of the same type (the separated scheme) or of different types (the unified scheme) if the most stringent quality of service (QoS) amongst traffic of different types is used on the VP. In addition, VP capacity is dynamically adjusted in a predetermined incremental size. In this paper, we study a least loaded path-based adaptive routing algorithm called maximum free circuit routing under two bandwidth allocation schemes, in an ATM network employing the VP concept. In particular, we evaluate the call blocking probability and the call set-up processing load with varying bandwidth incremental sizes. It is found numerically how the use of VP trades the blocking probability for call setup processing load. It is also found that the unified scheme could outperform the separated scheme with the use of VP.