How this Chapter Is Organized
Figure 1-3
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Narrow Band and Cell Bus Service Modules
A cell bus service module (CBSM) is an MGX service module that uses the MGX cell bus to transport
customer traffic between that service module and other service modules or PXM uplinks. Traditionally,
the CBSM cards were called narrow band service modules (NBSMs) because some AXSM cards (which
use the MGX serial bus) support higher rate communications. AXSM cards run only in MGX 2 (and
later) switches, and until MGX Release 3, the CBSM cards ran only in MGX 8850 (PXM1). So the
purpose of the NBSM term was to collectively refer to all cards that ran in MGX 8850 (PXM1) and MGX
Cisco MGX 8800/8900 Series Hardware Installation Guide
1-6
Bay and Line Numbers in an MGX 8850 Switch
SMB-6T3
ENABLED
RX
PORT 1
TX
RX
PORT 2
TX
RX
PORT 3
TX
RX
PORT 4
TX
RX
PORT 5
TX
RX
PORT 6
TX
SMB-6T3
ENABLED
RX
PORT 1
TX
RX
PORT 2
TX
RX
PORT 3
TX
RX
PORT 4
TX
RX
PORT 5
TX
RX
PORT 6
TX
Bay 1
Slot 14
Bay 2
Releases 2 - 5.2, Part Number OL-4545-01, Rev. H0, May 2006
Chapter 1
Product Overviews