Nortel Networks OPTera Metro 3500 - Manual (Page 311)

Hardware feature descriptions 3-83
Planning and Ordering Guide—Part 1 of 2 NTRN10AN Rel 12.1 Standard Iss 1 Apr 2004
Equipping rules
Connectivity for the 3 EC-1 signals at each slot is through the BNC 12-Port
Front I/O module (NTN452JA) on the OPTera Metro 3500 Shelf
(NTN476DA). On the OPTera Metro 3500 Universal Shelf (NTN476AH) you
must use the BNC 12-Port Front Enhanced I/O module (NTN452JH) or the
BNC 12-Port Rear I/O module (NTN452KA).
The EC-1x3 circuit pack can be installed in slots 3 through 10. EC-1x3 circuit
packs are installed in pairs. The first EC-1x3 circuit pack of the pair is installed
in an odd slot. The second EC-1x3 circuit pack of the pair is installed in the
adjacent even slot. The second EC-1x3 circuit pack functions as the protection
EC-1x3 circuit pack for the working circuit pack in the odd slot.
The maximum number of working EC-1x3 circuit packs that can be inserted
in a shelf is four.
See Table 3-3 on page 3-6 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 EC-1x3 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 EC-1x3 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 EC-1x3 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
EC-1x3 protection switching is 1+1 non-revertive. If a working EC-1x3 circuit
pack becomes defective, the traffic is switched to the protection EC-1x3 circuit
pack. Switching can also take place under user control.
Section data communication channel (SDCC)
An EC-1 line carries a DCC channel that can be edited, provisioned, and
deprovisioned. An EC-1x3 circuit pack can only carry one SDCC channel,
provisionable on any of the three EC-1 ports.
Note 1: The maximum number of simultaneous SDCC-provisionable
ports on an OPTera Metro 3500 shelf is 34 (the shelf must be equipped with
eight unprotected OC-3x4 or OC-12x4 STS circuit packs in slots 3 through
10, and a protected pair of OC-48 or OC-192 circuit packs in slots 11 and
12).