Protection switching, Protection switching 3-88 – Nortel Networks OPTera Metro 3500 User Manual
Page 316
3-88 Hardware feature descriptions
OPTera Metro 3500 Multiservice Platform NTRN10AN Rel 12.1 Standard Iss 1 Apr 2004
DS3x3 mappers are installed in pairs and DS3 protection switching is 1+1
non-revertive.
The DS3x3 circuit pack can be installed in slots 3 through 10. DS3x3 circuit
packs are installed in pairs. The first DS3x3 circuit pack of the pair is installed
in an odd slot. The second DS3x3 circuit pack of the pair is installed in the
adjacent even slot. The second DS3x3 circuit pack functions as the protection
DS3x3 circuit pack for the working circuit pack in the odd slot.
The maximum number of working DS3x3 circuit packs that can be inserted in
a shelf is four.
See
for operational temperature ranges.
Note 1: If there is a 1-28 DS1 I/O module installed, and if slots 5 and 6 are
not equipped with DS1 mappers, you may not install DS3x3 circuit packs
in slots 5 or 6 (there is not enough room for slot 5 or slot 6’s BNC I/O
modules).
Note 2: If there is a 29-56 DS1 I/O module installed, and if slots 7 and 8
are not equipped with DS1 mappers, you may not install DS3x3 circuit
packs in slots 7 and 8 (there is not enough room for slot 7 or slot 8’s BNC
I/O modules).
Note 3: If there is a 29-84 DS1 I/O module installed, and if slots 7 through
10 are not equipped with DS1 mappers, you may not install DS3x3 circuit
packs in slots 7 through 10 (there is not enough room for slot 7 through slot
10’s BNC I/O modules).
Protection switching
DS3x3 protection switching is 1+1 non-revertive. If a working DS3x3 mapper
becomes defective, the traffic is switched to the protection DS3x3 mapper.
Switching can also take place under user control.
Alarm LED definitions
The following table provides a list of LEDs of the DS3x3 mapper. See
for the DS3x3 mapper faceplate layout showing the location
of the LEDs.
LED
Color
Description
Status (top)
Red
Circuit pack failure
Status (bottom) Green
DS3x3 equipment is active and at least one DS3 line
facility is in service with at least one cross-connect
LOS (1-3)
Yellow
Loss of signal on the port