OAM Alarms and Loopbacks
64 Avidia System Configuration and Management User Manual
ATM Switch to Modem Segment or End-to-End Loopback The ATM switch to modem segment or end-to-end loopback test originates and terminates at
an ATM switch (point C). The loopback target or destination is the modem (point A), as shown
in the figure below. The loopback verifies a PVC from an ATM switch through to the modem.
In this test that originates at the ATM switch, the Avidia system is a passive ATM device; that
is, it simply passes the OAM F4 or F5 flow test cells, generated by the ATM switch,
transparently to the modem.
To perform this test, the user must be familiar with the OAM commands for the ATM switch.
The user must specify the:
•VPI/VCI for an OAM F5 flow VCC or VPIon ly for an OAM F4 flow VPC (for the test
which is sent to the Avidia-to-switch interface)
•destination or target Location ID address (as defined at Point A) for an OAM loopback may
be required by some ATM switches (the modem does not have a Location ID so you can
leave the Destination Location ID as a default value if that value is different than the OAM
Location ID for the Avidia system)
Point C
ATM LinkADSL Loop
Avidia System
Megabit Modem
MEGABITMODEM
Point A OAM Segment or End-to-End Loopback
ATM
Switch