VPN Terminology
MAC-VRF: A virtual routing and forwarding table for storing MACs on a PE for specific bridge domain.
CE: Customer Edge device, e.g., a host, router, or switch.
PE: Provider edge device
EVI: An EVPN instance spanning the Provider Edge (PE) devices participating in that EVPN.
Note: Ethernet Segment (ES): Set of Ethernet links connected between CE and PE. Single CE can be connected to multiple PEs.
Ethernet Segment Identifier (ESI): A unique non-zero identifier that identifies an Ethernet segment is called an ESI
Ethernet Tag: An Ethernet tag identifies a particular broadcast domain, e.g., a VLAN. An EVPN instance consists of one or more broadcast domains.
Benefits
The EVPN control-plane MAC learning has the following benefits:
• Eliminate flood and learn mechanism as hosts are learned over control plane.
• OcNOS supports both dynamically learned hosts and statically configured hosts, which are advertised/learned over the EVPN control plane.
• Fast-reroute, resiliency, and faster convergence in case of multihoming
• Load balancing of traffic to and from CEs that are multihomed to multiple PE's.
The following EVPN types are supported:
• Single-homed CE: One CE is connected to One PE device.
• Multihomed CE: One CE is connected to Multiple PE devices. OcNOS supports dual-homed CEs with all- active multi homing mode.
Route Types
These EVPN route types are supported:
• Route Type 1: Ethernet Auto-Discovery (AD) Route
The Ethernet (AD) routes are advertised on per EVI and per ESI basis. These routes are sent per ES. They carry the list of EVIs that belong to the ES.
This route is advertised when multihomed CEs already exist.
• Route Type 2: MAC/IP Advertisement Route
The host's IP and MAC addresses are advertised to the peers within NLRI. The control plane learning of MAC addresses reduces unknown unicast flooding.
• Route Type 3: Inclusive Multicast Ethernet Tag Route
This route establishes the connection for broadcast, unknown unicast, and multicast (BUM) traffic from a source PE to a remote PE.
This route is advertised on per VLAN and per ESI basis.
• Route Type 4: Ethernet Segment Route
Ethernet segment routes enable to connect a CE device to two or PE devices.
Ethernet segment routes enable the discovery of connected PE devices that are connected to the same Ethernet segment.
EVPN auto route target will be supported under MAC VRF.
In EVPN-VPWS the auto-discovery of peer PE nodes is done with the pair of Ethernet A-D routes. Inclusive Multicast route does not have participation on auto-discovery unlike ELAN-EVPN VPLS. Since there is no mac-advertisement, MAC-IP route is not applicable
Note: Only Sub-interface supported as Access-port for EVPN-MPLS.
Last modified date: 10/17/2023