Nortel Networks BCM200/400 - Manual (Page 45)

Chapter 2 Introducing the BCM hardware 45
BCM200/400 4.0 Installation and Maintenance Guide
MSC IP call processing hardware
If your system requires a high volume of IP telephones or more IP trunks than the standard eight
trunks, you can switch a DS30 bus setting on the MSC from providing service for an MBM, to
providing digital processing service for additional IP telephones and trunks. To ensure adequate
data flow from the system, you can increase the number of PEC III cards (BCM200 can have
maximum of two cards; BCM400 can have a maximum of four).
• DS30 buses: DS30 buses contain internal communication paths. Each DS30 bus provides up
to 32 signaling channels and 32 media channels.
— Two DS30 buses are exclusively dedicated to MSC data resources. Five paths within these
buses have hard-coded applications. The other paths can be assigned to various data
applications, such as voice mail, dialup ISDN WAN, VoIP trunks, or IP telephony.
— Five DS30 buses are exclusively reserved for the MBMs.
— One DS30 bus can be switched to accommodate MBMs or more channels for IP
telephones or VoIP trunks. You control the use of this bus by using either a 2/6 or 3/5
DS30 bus split. This is set when you configure the system.
• PEC IIIs: PEC IIIs increase the digital signal processing capacity for voice mail, call center,
fax, VoIP trunks, IP telephony, and dial-up ISDN WAN features. The BCM200 system uses
one PEC III card (expandable to two). The BCM400 system uses two PEC IIIs (expandable to
four) to accommodate increased requirements for media processing.
Main card
The main card contains several field replaceable units (FRUs), such as the RAM, modem card, and
CMOS battery. A riser card, set at right angles to the main card, provides connections for the MSC
and a field-installed wide area network card (WAN).
Figure 12 shows the layout of the main card
as installed in the base function tray.