Alcatel-Lucent 6850-48 Guida Di Rete

Pagina di 1162
Interaction With Other Features
Configuring EFM (LINK OAM)
page 16-8
OmniSwitch AOS Release 6 Network Configuration Guide
September 2009
Remote Loopback Testing
Remote loopback, which is often used to troubleshoot networks, allows one node to put the other node into 
a state whereby all inbound traffic is immediately reflected back onto the link. Remote loopback is most 
useful as a diagnostic tool, where it can be used to isolate problem segments in a large network. 
By performing remote loopback tests periodically, network administrators can detect network faults in 
time and also isolate the network segments where errors have occurred.
Remote loopback testing in networks can be done only after the LINK OAM connection is established. 
With remote loopback enabled, the LINK OAM node operating in active LINK OAM mode issues remote 
loopback requests and the peer responds to them. If the peer operates in the loopback mode, it returns all 
the PDUs except Ethernet OAMPDUs to the senders along the original paths. 
For enabling or disabling remote loopback process on a port, see 
 
Interaction With Other Features
This section contains important information about how other OmniSwitch features interact with LINK 
OAM. Refer to the specific chapter for each feature to get more detailed information about how to config-
ure and use the feature.
Link Aggregate 
LINK OAM will not work on the logical link aggregate port. But, it can run on the individual aggregable 
(physical) port.
Connectivity Fault Management
Connectivity Fault Management (IEEE 802.1ag) covers the scope of Ethernet service over any path, 
whether a single link or end-to-end, enabling service providers to fully monitor Ethernet service regard-
less of the layers supporting the service, the network path, or the various network operators involved. It 
divides a network into maintenance domains in the form of hierarchy levels, which are then allocated to 
users, service providers and operators. 
Connectivity Fault Management (CFM) assigns maintenance end points (MEPs) to the edges of each 
domain and maintenance intermediate points (MIPs) to ports within domains. This helps to define the rela-
tionships between all entities from a maintenance perspective, to allow each entity to monitor the layers 
under its responsibility and localize the errors easily.
ERP 
LINK OAM is supported in Ethernet Ring Protection (ERP) switching mechanism. ERP (ITU-T G.8032/
Y.1344) is a self-configuring algorithm that maintains a loop-free topology while providing data path 
redundancy and network scalability. ERP provides fast recovery times for Ethernet ring topologies by 
utilizing traditional Ethernet MAC and bridge functions..