Optimised Multi Homing - an Approach for Inter-domain Traffic Engineering

Traffic engineering (TE) has been widely investigated in recent years. Though, the scope of these works were predominantly limited to intra-domain TE and single administrative domains. Not even the long term TE with monitoring and analysis of traffic exchange points has been adequately solved, not to mention the short term, real-time performance related inter-domain TE tasks. This is in spite of the fact that today’s operators acknowledge that the edges of their networks where they pass traffic to other domains is the source of their greatest costs, which demands effective management of their inter-domain traffic. In this article, the authors argue that the first simplest step towards inter-domain TE could be the distribution of load towards one destination prefix among the possible alternative egress links. This is achieved by having more than one connection in the domain to the outside world; commonly known as multi-homing. The authors propose a network model and several algorithmic approaches to capture, incorporate and utilise the advantages given by multi-homing into the intra-domain TE objectives. Numerical evaluation of the different proposals compared to traditional shortest path first routing is also performed.