Enhancing OSPF to provide adaptive traffic distribution with networks for improved QoS performance

Tasir, ARM 2007, Enhancing OSPF to provide adaptive traffic distribution with networks for improved QoS performance , PhD thesis, University of Salford.

[img] PDF
Restricted to Repository staff only until 31 July 2022.

Download (93MB) | Request a copy


In recent years the growth in demand for multimedia applications delivered over a network has been extensive illustrated by the phenomenal expansion of the World Wide Web in today's Internet. Increasing amounts of electronic information are presented in a multimedia format and delivered over networks, which generates increased traffic demands. In short, future networks will not only comprise multiple, interconnected data transport platforms but will also need to handle an increasing range of distributed multimedia services, delivered to a diverse user community that is increasingly becoming mobile. However, this vision can only be realised if the underlying network infrastructure is capable of providing the appropriate Quality of Service (QoS) guarantees. The only limitation is that bandwidth will always remain a finite resource and whilst 'throwing bandwidth' at the network may provide short-term relief, in the medium and long term, users grow their demand to equal and finally surpass the capacity of the network. As the network is a finite resource, effective usage is very important without compromising the applications in the process. Thus, a substantial body of research is being conducted into the development of QoS routing policies, which are able to direct traffic over a connectionless, best effort delivery platform whilst trying to satisfy the end-to-end application's QoS requirements. In existing IP data networks, routing is concerned with connectivity and typically supports only one type of datagram service called "Best Effort Routing". Routing protocols such as OSPF in the main only use shortest-path algorithms and an arbitrary single metric such as hop count, for optimal path computation. Therefore, routing protocols need to have a more complex model to support QoS requirements. The basic problem of QoS-based routing is then to find a path that satisfies multiple QoS constraints and resource utilisation efficiency. This thesis reports on research work that has investigated how OSPF can be enhanced to provide an adaptive traffic routing algorithm that aims to assign, and dynamically reassign, traffic flows to routes based on current utilisation. In this way overall traffic can be more efficiently distributed across the network topology, thereby delaying the onset of congestion and improving overall end-to-end delay times. A new traffic distribution algorithm has been developed and integrated within OSPF. This, in turn, has been simulated using the OPNET Modeler® simulator and proven to offer improved QoS performance over standard OSPF. Studies have also been carried out to evaluate behavioural characteristics of the new algorithm resulting from the dynamic reassignment of traffic flows. Whilst the implementation has concentrated on OSPF, the work has broader application to other routing protocols. In conclusion, a new adaptive traffic distribution algorithm is proposed to enhance the performance of OSPF and hence, contribute to the broader body of knowledge in field of QoS based routing.

Item Type: Thesis (PhD)
Contributors: Linge, N (Supervisor)
Schools: Schools > School of Computing, Science and Engineering
Depositing User: Institutional Repository
Date Deposited: 19 Aug 2021 10:08
Last Modified: 27 Aug 2021 21:57
URI: http://usir.salford.ac.uk/id/eprint/61647

Actions (login required)

Edit record (repository staff only) Edit record (repository staff only)


Downloads per month over past year