Advertising Equal Cost Multipath routes in BGP

This document describes an extensible mechanism that will allow a BGP [BGP4] speaker to advertise ECMP routes for a destination to its peers. It uses an existing, Multi Hop Capability [M-HOP], to advertise multiple paths that it is using to its peers. The mechanism described in this document is only applicable to routers that have the ability to inject multiple routing entries in their forwarding table.