Ethernet OAM Overview

The 7705 SAR supports the following Ethernet OAM capabilities:

• Ethernet Connectivity Fault Management (ETH-CFM) — for network layer OAM according to IEEE 802.1ag (dot1ag) and ITU Y.1731 standards, including loopback (LB), linktrace (LT), continuity check (CC), and remote defect indication (RDI). "Network layer" refers to an end-to-end context across a network.

  ITU-T Y.1731 provides functional enhancements to 802.1ag ETH-CFM, including alarm indication signals (AIS) and Ethernet signal tests (ETH-Test).

  See ETH-CFM Ethernet OAM Tests (802.1ag and Y.1731).

• Performance Monitoring (PM) — PM according to the ITU-T Y.1731 standard, including delay measurements (DM), delay variation measurements (DV), and loss measurements (LM)

  See ITU-T Y.1731 Performance Monitoring (PM).

• Ethernet Bandwidth Notification (ETH-BN) — when enabled on a port, the egress rate may be dynamically altered based on the available bandwidth indicated by the ETH-BN server.

  See ITU-T Y.1731 Ethernet Bandwidth Notification (ETH-BN).

• Ethernet First Mile (EFM) OAM — for the transport layer OAM according to IEEE 802.3ah (dot3ah) standards. "Transport layer" refers to a point-to-point link context or transport hop.

  See EFM OAM (802.3ah).

Ethernet OAM capabilities on the 7705 SAR are similar to the OAM capabilities offered in SONET/SDH networks and include loopback tests to verify end-to-end connectivity, test pattern generation (and response) to verify error-free operation, and alarm message generation in case of fault conditions to ensure that the far end is notified of the failure.

Ethernet OAM configurations are maintained across CSM switchovers.