Description: An entry of sonusAtmExtOamF5Table which is used to provide OAM feature for Virtual circuit in this ATM interface. Three major OAM functions are supported in this MIB entry. The first function is the Loopback capability for this virtual circuit which includes both of End2end Loopback and UNILoopback. The second function is the OAM continuity capability for this virtual circuit which uses Loopback cells to transmit periodically. Transmit and recieve loopback cell statisitics can be used to determine if there is continuity. The third function is basic fault management feature using AIS/RDI cells to inform the upstream/downstream failure condition, the counters are used to keep failure statistics.