Ethernet Raw Mode Encapsulation for Martini Layer 2 Transport Overview

An Ethernet pseudowire carries Ethernet/802.3 traffic over an MPLS network. JunosE Software enables Ethernet traffic to be transmitted over Martini circuits (cross-connect virtual circuits) on ES2 4G line modules (LMs), GE-2 LMs, GE/FE LMs, ES2 10G LMs, ES2 10G Uplink LMs, and ES2 10G ADV LMs. The transfer of Ethernet packets over MPLS-based pseudowire enabled service providers to provide point-to-point layer 2 Ethernet connectivity between geographically remote customer edge (CE) devices. This functionality enabled the following tasks to be performed on received packets:

However, this mode of processing did not allow for:

You can configure an S-VLAN subinterface to enable the provider edge (PE) device to strip the S-VLAN tag from all packets that enter the MPLS pseudowires or Martini circuits. This functionality is also referred to as operation of Martini circuits or MPLS shim interfaces in raw mode. An Ethernet pseudowire can operate in either tagged mode or raw mode.

You can enable the raw mode configuration only for MPLS shim interfaces stacked on S-VLAN interfaces. Unified ISSU and high availability are supported when the router is configured in either of these ways:

Note: You cannot enable the raw mode configuration for S-VLAN subinterfaces on the ES2 10G, ES2 10G ADV, and ES2 10G UPLINK LMs.

When a pseudowire operates in raw mode, service-delimiting tags, if present in the frame received from the PE device, are stripped from the frame before being sent to the next processing point in the circuit. The Ethernet frame is encapsulated according to the algorithm defined for raw mode. If the local PE device detects a failure on the Ethernet input port, or if the port is disabled, the PE device sends an appropriate pseudowire status notification message to the remote PE device. In raw mode, all Ethernet frames received on the local PE device are transmitted to the remote PE device on a single pseudowire. The raw-mode attribute of the Martini circuit is sent to the forwarding controller (FC) on the supported line modules and the Label Distribution Protocol (LDP) is notified of the correct pseudowire type to be used in the signaling messages.

Related Documentation