An engineer must provide Layer 2 adjacency between data centers that are in two locations and separated by a routed network. The adjacency must be based on Cisco Nexus 7000 Series Switches. The soluti

VXLAN EVPN (Ethernet VPN) provides Layer 2 adjacency over a routed network by utilizing BGP EVPN as a control plane to distribute MAC address and IP address reachability information. This control plane learning eliminates excessive data-plane flooding for unknown unicast, broadcast, and multicast traffic, thereby mitigating unknown unicast congestion and improving scalability compared to pure data-plane learning solutions.

OTV (Overlay Transport Virtualization) also provides control plane learning and reduces flooding, but VXLAN EVPN with its BGP control plane offers a more modern and scalable solution for general DCI and is explicit in its mitigation of unknown unicast via control plane distribution.

VPLS (Virtual Private LAN Service) typically relies on full-mesh signaling or data-plane learning, which does not effectively offload learning to a control plane in the same way as VXLAN EVPN or fully mitigate unknown unicast flooding.

LISP (Location/ID Separation Protocol) is primarily designed for host mobility and routing scalability in IP networks, separating endpoint identities from their routing locators, and is not a primary Layer 2 DCI technology for providing direct adjacency with control plane learning characteristics described.