Four Data Center InterConnect (DCI) options for EVPN-VXLAN service are described in detail in the Advanced Data Center Switching (ADCX) course materials.

These options are:

• EVPN-VXLAN session over L3VPN-MPLS service;
• EVPN-VXLAN to EVPN-MPLS stitching;
• EVPN-VXLAN to EVPN-VXLAN stitching;
• EVPN-VXLAN session over dark fiber.

First and last options are not so interesting – simple EVPN-VXLAN session between DC devices over direct IP connectivity or via L3VPN service. Basic L3VPN/MPLS stuff.

But EVPN stitching is a slightly different story. Resembles Inter-AS VRF Option-A. Two EVPN domains are connected via Logical Tunnel (lt-) interfaces on MX device. Not very complex, but requires a lot of configuration. See it in the next post.