New Bandwidth Management Framework for Supporting Differentiated Services in MPLS Networks

This paper presents a new bandwidth management framework supporting differentiated services aware traffic engineering (DSTE) in the multi-protocol label switching (MPLS). Our bandwidth management framework contains route computation, bandwidth allocation and preemption for label switched paths (LSPs). We put forward two algorithms. The first one, named bandwidth preemption algorithm, dedicated for the maximum allocation model and in which preemption is conducted in two dimensions: Class Type and priority levels within a same CT. Furthermore, we design a second algorithm named LSP preemption algorithm to select the most appropriate LSPs to be cast out. Selection decision is made on the basis of several criteria: the precedence level, the number of LSPs to preempt and the excess of bandwidth to gain. Extensive simulation study is carried out to evaluate the performance of our approach. Compared with existing ones, our algorithm improves not only bandwidth efficiency but also robustness and fairness. It achieves significant performance improvement for the well-behaving traffic classes in term of bandwidth link utilization, bandwidth blocking,and LSPs preemption.