Chapter3: Applications and Configuration Overview
Avidia System Configuration and Management User Manual 65
ATM Switch to Avidia Line Card Segment Loopback
The ATM switch to Avidia line card segment loopback originates and terminates at the source
ATM swit ch (point C). The loopback target or destination is the Avidia line card (point B),

asshown in the figure below. At the ATM switch, the user must specify for this test the:

•VPI/VCI for an OAM F5 flow VCC or VPI only for an OAM F4 flow VPC
•OAM Destination Location ID for the Avidia system
ATM Node to Modem Segment or End-to-End Loopback
The ATM node (beyond the ATM switch) to modem segment or end-to-end loopback test
originates and terminates at an ATM node (point D). The loopback target or destination is
themodem (point A), as shown in the figure below. The loopback verifies a PVC from an
ATM node through to the modem. In this test that originates at the ATM node, the Avidia
system is apassive ATM device; that is, it simply passes the OAM F4 or F5 flow test cells,
generated by the ATM switch, transparently to modem.
Point C
ATM Link
Avidia System
Point B - line card
OAM Segment Loopback
ATM
Switch
ATM LinkADSL Loop
Avidia System
Megabit Modem
MEGABITMODEM
Point A OAM Segment or End-to-End Loopback
ATM
Switch
Point D
ATM node