Ethernet VPN (EVPN) is a next generation solution that provides Ethernet multipoint services over MPLS networks.
EVPN operates in contrast to the existing Virtual Private LAN Service (VPLS) by enabling control-plane based MAC learning in the core. In EVPN, PE’s participating in the EVPN instances learn MAC routes in Control-Plane and IP addresses using MP-BGP protocol. Control-plane MAC learning brings a number of benefits that allow EVPN to address the VPLS shortcomings, including support for multi-homing with per-flow load balancing. The EVPN control-plane MAC learning has the following benefits: • Eliminate flood and learn mechanism. • MAC Mobility. • Fast-reroute, resiliency, and faster network convergence. • Enables load balancing of traffic to and from CEs that are multi-homed to multiple PEs. • Fast convergence to minimize downtime and packet loss.
The following table shows a comparison of some key points for EVPN/MPLS and VPLS:
| Feature | EVPN/MPLS | VPLS |
| Use MPLS Transport | Yes | Yes |
| Protocol Evolution (Design Life) | Next Generation | Legacy |
| MPLS Fast Reroute (FRR) < 50ms | Yes | Yes |
| L2 Stretching | Yes | Yes |
| L3 Routing Integration | Yes, Integrated Routing andBridging (IRB). Single VPN technology for L3 and L2 VPNs. | No |
| VLAN Design | Flexible. Significant to the location. | Flat VLANs extended across locations can impact performance. |
| High Exposure to Broadcast Storms | No | Yes |
| DoS Attack Probability | Low | High |
| L2 PDUs must be tunnelled across MPLS Core, such as Spanning Tree (STP) BPDUs | No | Yes |
| Broadcast, Unknown Unicast and Multicast (BUM) Traffic | Suppression of BUM traffic at the PE device (locally). | Multicast and broadcast radiation to all sites. |
| MAC Address Learning | Control Plane (more efficient and scalable). | Data Plane (scalability considerations/limitations). |
| BGP to advertise MAC/IP info | Yes | No |
| Multi homing Active-Active per Flow | Yes | No |
| Multi homing Active-Standby per VLAN/Service | Yes | Yes |
| MAC Mobility | Yes | No |
| MAC Mass-Withdraw for fast convergence | BGP Based Withdraw. | LDP/BGP Based Withdraw. |
| Seamless VM Mobility | Yes | No |
| QoS Support | Yes | Yes |