L2VPN Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

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Layer 2 virtual private networks

Updated: June 15, 2026

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Outlines the core concepts of Layer 2 virtual private networks, detailing L2VPN service requirements, supported interface types, and the primary benefits of deploying L2VPN solutions in modern network environments.

A Layer 2 virtual private network (L2VPN) is a private Layer 2 service that

  • emulates a physical sub-network in an IP or MPLS network

  • creates private connections between two points, and

  • helps maintain customer privacy while using service provider resources to establish the network.

Requirements for L2VPN network deployment

To successfully deploy an L2VPN network, these requirements and capabilities are essential:

  • Layer 2 connectivity coordination: The service provider establishes Layer 2 connectivity, while the customer uses these data link resources to build their own network.

  • Customer network privacy: The service provider does not require knowledge of the customer's internal network topology, helping maintain customer privacy.

  • Provider edge router capabilities: Provider edge (PE) routers must support encapsulation of Layer 2 protocol data units (PDUs) into Layer 3 packets, interconnection of any-to-any Layer 2 transports, MPLS tunneling mechanisms, and processing databases for circuit and connection information.

  • Hardware support: Line cards and routers equipped with Q100, Q200, and P100-based Silicon One ASICs provide support for L2VPN services.

These requirements ensure successful and secure L2VPN deployment that meets both service provider and customer needs.

L2VPN interface types and key attributes

L2VPN interfaces enable service providers to deliver Layer 2 connectivity between geographically separated customer sites. The main interface types used in L2VPN networks, along with their attributes, are:

  • Attachment circuit (AC): Connects the customer site to the service provider's edge router, carrying Layer 2 traffic.

  • Provider edge (PE) interface: Terminates the AC at the service provider's edge router and handles forwarding to the core.

  • Core tunnel interface: Tunnels traffic from the PE router across the service provider core to reach another PE router.

Key facts about L2VPN interfaces:

  • Each customer site connects to the nearest service provider edge router through an AC.

  • Traffic from one customer site can be carried through the AC into the service provider core, traversing the core tunnel interface to reach another edge router.

  • The receiving edge router uses another AC to deliver traffic to the remote customer site, maintaining Layer 2 connectivity across wide geographic distances.

Benefits of Layer 2 virtual private networks

  • Allow service providers to consolidate both Layer 2 and Layer 3 services onto a single infrastructure, simplifying network management and operations.

  • Enable cost-effective delivery through a converged IP or MPLS network, reducing expenses associated with maintaining separate systems for different service types.