Nortel Networks BCM200/400 - Manual (Page 64)

64 Chapter 2 Introducing the BCM hardware
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Specialized media bay modules (MBMs)
This section describes the MBMs that perform a specific job outside of the trunk and station MBM
descriptions (see
Table 11 ).
Fiber expansion media bay module
The fiber expansion media bay module (FEM) connects a maximum of six Norstar MBMs to the
BCM system. These connections provide a quick way to upgrade a Norstar system to a BCM
system.
The front bezel of the FEM has six connectors. These connections are made using fiber cables
between the FEM module and the Norstar expansion unit.
Figure 35 shows the front of the FEM module. Each enabled port consumes one DS30 bus.
Figure 35 FEM faceplate LEDs and connectors
Digital drop and insert MUX
The digital drop and insert MUX media bay module (DDIM) enables a BCM system to share its
connection to a universal T1 network with a local area network (LAN) to provide a combination of
voice and data channels.
The DDIM:
Table 11 Specialized MBMs
Module type What it does Special notes
FEM
(see “Fiber expansion
media bay module” on
page 64
)
Connects a maximum of six Norstar expansion
units. The switches on the FEM are used to
turn fiber ports on and off. The FEM
does not work correctly if you set these
switches using the rules used for other
MBMs.
DDIM
(see “Digital drop and
insert MUX” on page
64
)
Enables a BCM system to share its connection to a
universal T1 network with a LAN.
Front view
Port 4
Power LED
Status LED
Port 1
Port 5
Port 2
Port 6
Port 3
4 5 6
3 2 1
FEM