BGP EVPN Overview

RFC 7432 (BGP MPLS-Based Ethernet VPN) specifies multiprotocol extensions to BGP to exchange Layer 2 routes in an MPLS Ethernet VPN network. These extensions are useful in DCI scenarios.

A BGP EVPN-based IP Fabric consists of BGP EVPN for VxLAN overlay networks and a broad set of Layer 2, Layer 3, and infrastructure features to enable seamless deployment, on-demand usage of forwarding entries in hardware, and minimization of flooding in the network.

IP Fabrics topologies

The following figure shows a supported topology where the SLX devices are nodes in a BGP EVPN spine in an IP Fabrics network.

Supported BGP EVPN spine topology

The leaf nodes in the IP Fabric can be any of the supported hardware platforms. A BGP EVPN-based Multi-Chassis Trunk (MCT) solution is also supported on those platforms. However, using a co-located BGP EVPN spine and a BGP EVPN MCT on the same switch is not supported. For a list of supported platforms, see Supported Hardware.

VxLANs provide the inter-connectivity between leaf nodes in an IP Fabric network. VxLAN tunnels are established between leaf nodes. The following figure illustrates this VxLAN connectivity.

VxLAN connectivity in an IP fabric
Note

Note

Leaf nodes will be dual-homed.

Supported IP Fabrics features

BGP EVPN use cases