Patent attributes
In one embodiment, a particular autonomous system border router (ASBR), in a control-plane media access control (MAC) learning (CPML) network, discovers other ASBRs in the CPML network, the particular ASBR and other ASBRs interconnected with respective ASBRs of a data-plane MAC learning (DPML) network. The particular ASBR calculates one or more internal shortest path first (SPF) trees rooted respectively at each of the other ASBRs in the CPML network, and upon receiving a MAC advertisement route for a given MAC address with a given next-hop IP address, it may determine a distance from the particular and each other ASBR in the CPML network to the given IP address based on the internal SPF trees. In response to the distance from the particular ASBR being shorter than the distance from each other ASBR, the particular ASBR is designated as a designated forwarder (DF) for traffic sourced from the given MAC address.