Specifications

Configuratio
n
5
0003097 Revision A 2
5
Digital Service Unit (DSU) Cabinet
A DSU cabinet holds up to four DSU cards and two FIMs. The DSU cards provide digital trunk
interfaces for public or private network access and specialized digital functions (such as
messaging, expanded conferencing, and ISDN service). The FIMs support the transmission of
voice and data signals between nodes.
The DSU cabinet consists of the following components:
• Cabinet Frame: The DSU cabinet is separated into two shelves. Shelf 1 is located at the
bottom of the cabinet and Shelf 2 is located at the top of the cabinet (both shelves are at
the front of the cabinet). Shelf 1 consists of slots 1 to 6 and contains 2 FIMs and 4 DSUs.
Shelf 2 consists of two Peripheral Resource Cards (PRCs).
• Power Supply: The 200 Watt AC or 150 Watt DC power supply provides power for the
cabinet. The power supply fan cools the cabinet.
• Peripheral Resource Cards: The
peripheral resource cards provide additional circuitry to
support the distributed architecture. These cards are installed in Shelf 2, slots 1 and 6.
• Fiber Interface Modules (FIMs): The DSU cabinet holds up to two
fiber interface modules
(FIMs). Each FIM supports two DSU cards; the FIM installed in Shelf 1, slot 1 supports
the DSU cards in Shelf 1, slots 2 and 3. The FIM in Shelf 1, slot 6 supports the DSU cards
in Shelf 1, slots 4 and 5.
• DSU Cards: The DSU cabinet holds up to four
DSU cards. These are intelligent cards
that provide specialized digital functions. The DSU cards are installed in Shelf 1, slots 2 to 5.