Understanding Route Aggregation

Date Added: Mar 2010
Format: PDF

Route aggregation, the method to supersede a set of routes by a single, more general route, is a universal mechanism that is either explicitly included in a routing protocol specification or added by router vendors as a configuration option. Widely deployed for both intra-domain and inter-domain routing purposes, Route Aggregation (RA) can be vulnerable to routing anomalies, and is fingered to be the cause of many reported loops and blackholes. In this paper, they posit that the problem arises from a lack of fundamental understanding of the RA mechanism. Moreover, the authors present the first rigorous and comprehensive analysis of route aggregation based on an abstract model. They show that the range of potential anomalies from RA configurations is much wider than previously documented.