In one embodiment, a method includes receiving, by a first autonomous system border router (ASBR) of a first autonomous system (AS), a first plurality of provider-provisioned media access control (B-MAC) addresses via Interior Border Gateway Protocol (I-BGP). Each of first plurality of B-MAC addresses is associated with a provider edge (PE) device of the first AS. The first ASBR sends the first plurality of B-MAC addresses to a second ASBR of a second AS using Exterior Border Gateway Protocol (E-BGP). The first ASBR also receives via E-BGP a second plurality of B-MAC addresses each of which is associated with a PE device of the second AS. The first ASBR then distributes the second plurality of B-MAC addresses to each of the PE devices of the first AS using I-BGP.