An Application of the BGP Community Attribute in Multi-home Routing

摘要

This document presents an application of the BGP community attribute[2] in simplifying the implementation and configuration of routingpolicies in the multi-provider Internet. It shows how the communitybased configuration can be used to replace the AS-based customizationof the BGP 'LOCAL_PREF' attribute, a common method used today. Notonly does the technique presented simplifies configuration andmanagement at the provider level, it also represents a paradigm shiftin that it gives the potential for the customer to control its ownrouting policy with respect to its service provider, as well asproviding the ability for policy configuration to be done at a prefixbased granularity rather than the more common AS based granularity.