Ntak93 D-Channel Handler Interface (Dchi) Daughterboard - Nortel Meridian 1 Option 11C Manual

Page 40 of 126 2.0 Mb PRI Implementation

NTAK93 D-Channel Handler Interface (DCHI) daughterboard

553-3011-315 Standard 13.00
Every cabinet that contains a digital trunk must contain a clock
controller. If a system is equipped with digital trunks, it is
recommended that at least one digital trunk be placed in the main
cabinet. If there is a mixture of TMDI and non-TMDI in the same
cabinet, place the clock controller on the non-TMDI card.
The Clock Controller circuitry synchronizes the Option 11C to an external
reference clock, and generates and distributes the clock to the system.
Option 11C can function either as a slave to an external clock or as a clocking
master. The NTAK20AB version of the clock controller meets AT&T
Stratum 3 and Bell Canada Node Category D specifications. The
NTAK20BB version meets CCITT stratum 4 specifications.
Shelf slot assignment
On non-CISPR B system cabinets, the NTAK20 may be placed in slots 1-9.
On cabinets NTAK11Dx and NTAK11Fx, the active NTAK20 must be
placed in slots 1-3 (slots 4-10 may not be used.) On IP Expansion cabinets,
the NTAK20 may be placed in slots 11-19, 21-29, 31-39, 41-49 of the first,
second, third, and fourth expansion cabinets, respectively.
The NTAK93 DCHI daughterboard interfaces with the Meridian 1 Option
11C Central Processing Unit (CPU) and mounts on the NTBK50 PRI card for
PRI (but not ISL) applications. The equivalent circuit is contained on-board
the NTAK79 2.0 Mb PRI card.
The DCHI is responsible for performing the Q.921 layer 2 protocol
information. It transfers layer 3 signaling information between two adjacent
network switches.
The NTAK93 DCH daughterboard, when installed on the NTBK50 circuit
card, is addressed in the same slot as the NTBK50.
January 2002
IMPORTANT