Figure C-1. Ethernet Oam (Carrier Ethernet; Ethernet Operation, Administration, And Management - ADTRAN Total Access 5000 Deployment Manual

Total Access 5000 Business Services Deployment Guide

Ethernet Operation, Administration, and Management

Two types of Ethernet Operation, Administration, and Management (OAM) are supported.
One type is Ethernet Link OAM defined by the IEEE 802.3ah standard. Ethernet Link OAM
operates over a single point‐to‐point Ethernet link. The other type is Ethernet Connectivity
Fault Management (CFM) defined by the IEEE 802.1ag standard. Ethernet CFM is used to
verify connectivity between endpoints across an Ethernet‐based network of any number of
links, and as faults occur, the device causing the failure can be determined through the use of
linktrace and loopback/ping messages.
Ethernet OAM Carrier Ethernet
Figure C‐1 shows a typical Total Access 5000 E‐Line deployment. Ethernet OAM is used in
this application to verify the entire Ethernet path between NetVanta #1 and NetVanta #2. If a
failure occurs at any point in the network, one (or both) NetVanta units will no longer receive
continuity check messages (CCMs) and will be able to raise an alarm. Once an alarm is
received, linktrace can be used to determine which devices can be seen along the path or to
target specific devices along the path. Using the layered capabilities of Ethernet OAM,
Ethernet OAM connections can exist between the two Total Access 5000 units or between the
two CPE routers; however, these would need to operate at different Maintenance Domain
(MD) levels.
The NetVanta 800/8000 supports creating Maintenance Association End Points (MEP) with the
following configurable attributes:
• Interface ‐ Any interface transporting Ethernet services.
• Direction ‐ Up or Down
• Component ‐ Provider or Customer
C-2
Demarcation
Customer
Site
NetVanta #1
CPE Router

Figure C-1. Ethernet OAM (Carrier Ethernet)

–Down MEP ‐ Active side is further away from MAC relay/Switch than its passive
side. A Down MEP transmits CFM messages from the interface it is on out to the
physical link.
–Up MEP ‐ Active side is further away from the interface it is on than its passive side.
An Up MEP transmits CFM messages from the interface is on in towards the MAC
relay of the bridge.
–Provider Component (S‐Component) ‐ A flow that is switched by s‐tag and defined
by an EVC.
Total Access 5000 #1 Total Access 5000 #2
Network
Link OAM 802.3ah
End to End OAM or multi-hop OAM
Demarcation
Customer
Site
NetVanta #2
802.1ag/Y.1731
65K510DEP08-1A
CPE Router