Figure 2: Intra-site unicastIntra-site unicast

As shown in the figure Figure 2: Intra-site unicast, the VTEP performs typical Layer 2 forwarding for known unicast traffic within the local site.

Figure 3: Inter-site unicast
Inter-site unicast
As shown in the figure Figure 3: Inter-site unicast, the following process applies to a known unicast frame between sites:
  1. The source VTEP encapsulates the Ethernet frame in the VXLAN/UDP/IP header.

    In the outer IP header, the source IP address is the source VTEP's VXLAN tunnel source IP address. The destination IP address is the VXLAN tunnel destination IP address.

  2. The source VTEP forwards the encapsulated packet out of the outgoing VXLAN tunnel interface.

  3. The intermediate transport devices (P devices) forward the packet to the destination VTEP by using the outer IP header.

  4. The destination VTEP removes the headers on top of the inner Ethernet frame. It then performs MAC address table lookup in the VXLAN's VNI to forward the frame out of the matching outgoing interface.