Centre for Communication Systems Research (CCSR), University of Surrey, Guildford, UK.
The current Internet consists of a large collection of Autonomous Systems (ASes) or domains, each being a network or group of networks managed by a single authority such as an Internet Service Provider (ISP), enterprise or university. These ASes employ their own network policies and routing protocols. Due to the remarkable increase in Internet traffic because of peer-to-peer content downloading, multimedia streaming, voice over IP, online gaming, video conferencing, etc., network providers seek to optimise the network resource usage in an efficient manner utilising Traffic Engineering (TE) techniques. These techniques control traffic routing so as to optimise operational IP network performance. TE techniques can be classified into intra-AS and inter-AS. Network providers use intra-AS TE techniques to control routing the traffic within their network to achieve objectives such as load balancing and/or minimising resource consumption. On the other hand, they use inter-AS TE techniques to control inbound and outbound traffic to achieve load balancing over inter-AS resources and/or minimising peering costs.Unfortunately, due to a variety of reasons such as malicious attacks, misconfiguration and accidental damage, various failures, and in particular link failures, occur as part of daily network operations. Recent research revealed that both single intra- and inter-AS link failure are common events and transient in nature. The potential impact of a link failure can be delay, packet discard, service disruption and severe congestion due to the shifting of an excessive amount of traffic to alternative paths that are already highly utilised. Given the short-lived nature of transient failures, network operators may not have sufficient time to re-configure their networks before the failure is restored, resulting to a detrimental failure impact. In order to manage this situation, in this thesis we propose proactive network provisioning approaches that predict the impact of transient link failures and implement remedy solutions to alleviate the detrimental failure impact. In fact, the contributions of our thesis are as follows:
Key words: Survivability, Robust Traffic Engineering, Intra- and Inter-AS Link Failure, Fast Recovery.
PhD Thesis, May 2008.
The full thesis in Acrobat pdf (1.43M) can be made available by contacting the author (mina.amin (at) live.co.uk).