Overlay Transport Virtualization (OTV), available with all F3-Series line cards, extends the data center layer 2 topology and connectivity to multiple data centers. It creates a single logical layer 2 network with VLANs extended across multiple data centers. The layer 3 OTV edge devices at each data center maintain a table with local and remote mac addresses. Remote host MAC reachability is done with a control plane protocol to advertise local MAC addresses to remote OTV edge devices. The remote MAC addresses have a next hop IP address of the remote OTV edge device. The OTV edge device uses MAC routing transport to encapsulate or add an IP header to the Ethernet layer 2 frame. The IP header contains the next hop IP address of the remote OTV edge device. The IP header is stripped off by the remote OTV edge device and forwarded to the core switch. At that point Ethernet frames are forwarded across the campus switching infrastructure with traditional data plane CAM and ARP table lookups.