DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126 Issue 4
June 1999
Maintenance Object Repair Procedures
9-849FIBER-LK (Fiber Link)
9
The following terms are used in the error descriptions:
LEDs for Circuit Packs on a Fiber Link
The yellow LEDs on the three types of boards, SNI (TN573), EI (TN570), and DS1
Converter (TN574 or TN1654), that may be a part of the fib er link can help in
diagnosing p roblems with the fiber link. The yellow LED states are as follows. The
flashing LED patterns take prec edence over the active or standby LED patterns.
If both endpoints of a fib er link (EI and/or SNI) are flashing with a fiber out of
frame pattern, a fast yellow LED pattern (0.1 sec ond on and 0.1 second off),
check the lightwave transc eivers (if present). Both lightwav e transceivers on the
fiber link must be of the same typ e. The 9823a shortwave transceiver and the
9823b longwave transceiver must never be combined on the same fiber link
because a fiber out of fr ame condition will exist. The 9823a lig htwave transceiver
should be used for d istances up to 4900 feet and the 9823b lightwave
transceiver should be use d for distances up to 25,000 feet.
Control Path The path between the two fiber end points that is necessary
for the two endpoint circ uit packs to c ommunicate.
Circuit Path The path between the two fiber end points that is necessary
for circuit switched phone calls to work.
Neighbor The circuit pack on the other en d of the fiber.
Out of Frame A circuit pac k reports fiber out of frame if it c annot detect
valid data coming from the fiber.
Packet Path The path betwe en the two fiber endpoint s that is necessary
for packet switched messages to be sent b etween the two
fiber endpoints.
Table 9-321. Switch Node Interface Yellow LED Flashing Codes
Condition LED on LED off
Fiber out of Frame 0.1 second 0.1 second
In Frame, No Neighbor1
1. The fiber is in frame, but no communic ation exists to the neighbor
0.5 second 0.5 second
SNI active Solid on Never off
SNI standby Never on Solid off