Performance evaluation of differentiated services over MPLS

Abstract

There is a compelling need to provide Quality of Service (QoS) within Internet with the introduction of multimedia applications, video conferencing etc. These applications demand high resource guarantees and timeliness of data. All the existing QoS architectures such as Differentiated Services, Integrated Services, Multi protocol label switching, Constraint based routing are designed to improve the overall performance of IP networks. But since Internet is a heterogeneous network the co-existence of these architectures provides means for the delivery of end-end QoS.

Differentiated services model provides QoS by dividing the trac into various service classes and providing service differentiation to each class of trac. MPLS is a label switching technology, that does not requires longest prefix matching, thereby providing fast forwarding of packets. This research work shows that MPLS and Diffserv integration is a good model to provide QoS in backbone networks. This integrated model is capable of providing service differentiation as well as fast forwarding. As a result of which delay, which is very crucial for real time applications, is reduced. In this work various QoS elements like token bucket, leaky bucket, WFQ scheduler etc. are implemented and tested. Diffserv domain is simulated and then MPLS is build on top of it. EXP inferred LSP, where all the classes are mapped onto the same label switched path, was used for mapping of Diffserv classes onto MPLS classes. The simulation results show that performance enhancement is achieved in terms of delay reduction as well as service differentiation when we integrate the two models.