Tag :: L2VPN

In an EVPN/VXLAN environment, ARP and IPv6 Neighbor Discovery (ND) bindings are typically learned only from packets addressed to the switch (via its SVI) or from broadcast traffic. This limits the switch's knowledge of hosts that request for SVI IP or hosts that send GARP. In addition to snooping packets requesting resolution for switch’s IP address, this feature enables the switch to learn and maintain ARP/ND bindings by snooping ARP and ND packets requesting resolution of IPs other than the switch’s IP, that are broadcast to other hosts through the switch.

Pseudowires can be used to connect geographically separated L2 networks by emulating an L2 point-to-point connection over a MPLS backbone. While each pseudowire can be configured manually, a L2VPN solution can be used to perform auto-discovery and signaling of the desired pseudowires. VPWS (Virtual Private Wire Service) can be used for auto-discovery and signaling of point-to-point pseudowires. The pseudowires in each VPWS instance can be signaled by LDP or BGP. When signaled using BGP, there are two VPWS sub-types:

In EVPN deployments, MAC address reachability is ascertained using both (i) MAC only routes, and (ii) MAC-IP routes. If all EVPN peers in the network are guaranteed to advertise a MAC-only route for MACs, then it is redundant to compute MAC reachability based on MAC-IP routes for the same MAC. With higher scale of the number of IPs mapped to the same MAC address, BGP best path work experiences a higher load.