In this paper, we present a traffic engineering technique that can be used by regional ISPs and customer networks. On the
basis of various characterizations of ASes in today’s Internet we show the requirements of the small ASes. Then we detail
the methods that such ASes currently use to engineer interdomain traffic. We present an analysis of real routing tables showing
that a lot of ISPs rely on the BGP Community attribute to build scalable traffic engineering configurations. We also show
that this solution suffers from several drawbacks that limit its widespread utilization. To avoid the problems of such a technique,
we propose the redistribution communities, a special type of non transitive extended community attribute and show that the
cost of implementing this solution is small.
This work was supported by the European Commission within the IST ATRIUM project.