Facility attributes, Loopbacks, Terminal loopback – Nortel Networks OPTera Metro 3500 User Manual
Page 92: Facility loopback, Facility attributes 2-54 loopbacks 2-54, Terminal loopback 2-54 facility loopback 2-54
2-54 Operation, administration, and maintenance (OAM) features
OPTera Metro 3500 Multiservice Platform NTRN10AN Rel 12.1 Standard Iss 1 Apr 2004
Facility attributes
Visible and provisionable facility attributes include the following:
•
Signal degrade threshold (SDTH)
•
Auto in service (AINS)
•
Section trace
•
Path trace
•
Equalization (DS1)
•
Frame Format (DS1)
•
Line build out (DS3, EC-1)
•
DS1, DS3, and EC-1 loopbacks
All supported facility attributes (except loopbacks) are default provisioned
when equipment is provisioned.
Loopbacks
Terminal loopback
A terminal loopback routes an incoming signal towards the backplane. An
alarm indication signal (AIS) is generated in the outward direction of the
signal.
Facility loopback
During a facility loopback, a signal received on the optical or electrical side of
the facility is looped back towards the associated return transmitter An alarm
indication signal (AIS) is generated in the onward direction of the signal. To
operate a facility loopback, the facility must be manually put out of service
(OOS).
Note: The facility must be out-of-service before a loopback is permitted
and both types of loopback cannot be active for a given facility at the same
time.
Facility loopback implementation complies with the latest issues of:
•
GR-253-CORE, Synchronous Optical Network (SONET) Transport
Systems: Common Generic Criteria
•
GR-819-CORE, Network maintenance: Access and Testing - Special
Services (SS) and SS-like networks
Refer to
for details on electrical loopback types.