L2CP Tunneling MEF

This chapter introduces you to L2 Control Protocols (L2CP) tunneling to help initiate control packets from a local customer-edge (CE) device to a remote CE device.

Table 1. Feature History Table

Feature Name

Release Information

Feature Description

L2CP Tunneling

Release 7.4.1

This feature is now supported on routers that have Cisco NC57 line cards installed and operates in native and compatibility modes.

L2 Control Protocols (L2CP) tunneling helps initiate control packets from a local customer-edge (CE) device to a remote CE device.

L2CP Tunneling

The router supports the following tunnel protocols:

  • Link Layer Discovery Protocol (LLDP)

  • Link Aggregation Control Protocol (LACP)

  • Operation, Administration, Management (OAM)

  • Ethernet Local Management Interface (ELMI)

  • Cisco Discovery Protocol (CDP)

Some of the L2 transport interfaces are:

  • VPWS L2 transport main

  • VPWS L2 subinterface

  • L2 transport main bridge port

  • L2 subinterface bridge port

  • VPWS L2 bundle main port

  • VPWS L2 bundle subinterface

  • L2 bundle main bridge port

On a subinterface, when control packets such as LLDP and LACP are tunneled, the system tunnels the same control packets to the main interface.

The LACP packet for VPLS (also known as ELAN service) either gets peered or dropped.

The router tunnels Layer 2 packets between PEs.

The following figure depicts Layer 2 protocol tunneling.

Figure 1. L2CP Tunneling

L2CP packets are tunneled from NNI to NNI (depicted in red pipe). The Layer 2 traffic is sent through the Cisco NCS Routers, and these routers switch the traffic from end to end.

Restrictions

  • VPLS service does not support LACP tunneling.

  • VPWS and EVPN-VPWS services support LACP tunneling.

L2CP Protocol Support on Cisco NCS Series Router

You do not need to configure L2CP tunneling explicitly. L2CP packets are tunneled over Layer 2 tunnel by default.

The following table lists the options that are supported on the router and displays the supported defaults and configuration options for the router.

Protocol

Packet Type

Action

CDP

Untagged

Peer

LACP

Untagged

Peer

LLDP

Untagged

Peer else Tunneled

STP

Untagged

Peer

VTP

Untagged

Peer

OAM

Untagged

Peer

BPDU

Untagged

Tunneled

UDLD

Untagged

Peer

CDP

Tagged

Tunneled

LACP

Tagged

Tunneled

LLDP

Tagged

Tunneled

STP

Tagged

Tunneled

VTP

Tagged

Tunneled

BPDU

Tagged

Tunneled

OAM

Tagged

Tunneled

ELMI

Tagged

Tunneled

UDLD

Tagged

Peer


Note


L2CP protocols over BVI is not supported.