4A0-115: Nokia Ethernet Virtual Private Network ServicesDemo

A-D per EVI routes (EVPN Route Type 1 advertised on a per-EVI basis) carry an Ethernet Tag ID of zero and a usable MPLS label, and each multihomed PE advertises one for every EVI instantiated on the Ethernet segment. Remote PEs use these advertisements to build aliasing lists so they can load-balance known-unicast traffic across all PEs attached to an all-active Ethernet segment, even if a destination MAC was learned from only one of them. What A-D per EVI routes do not do is discover the full set of PEs attached to a given Ethernet segment — that role belongs to the Ethernet Segment (Type 4) route, which is advertised per ESI and used by PEs to learn about each other and run Designated Forwarder election. Hence, describing per-EVI A-D routes as being used to discover all PEs associated with an Ethernet segment misattributes the Ethernet Segment route's function to the per-EVI A-D route, making that statement false.