Explicitly Accommodating Origin Preference for Inter-Domain Traffic Engineering

Abstract

Inter-domain traffic engineering is an important aspect of network operation both technically and economically. Traffic engineering the outbound direction is less problematic as routers under the control of the network operator are responsible for the way traffic leaves the network. The inbound direction is considerably harder as the way traffic enters a network is based on routing decisions in other networks. There are very few mechanisms available today that facilitate inter-domain inbound traffic engineering, such as prefix deaggregation, AS path prepending and systems based on BGP communities. These mechanisms have severe drawbacks such as an increase of the size of global routing table or providing only coarse-grained control. In this paper we propose and evaluate an alternative mechanism that does not increase the size of the global routing table, is easy to configure through a simple numeric value and provides a finer-grained control compared to existing mechanisms that also do not add additional prefixes to the global routing table.