7-2
Optical Services Modules Installation and Configuration Note, 12.2SR
OL-9465-03
Chapter 7 Configuring the Channelized 12-port CT3/T1 Optical Services Modules
Supported Features
Table 7-1
Serial Interface Cost
Channelized DS3 Overview
In the channelized mode of operation, an OSM-12CT3/T1 link is channelized into 28 DS1 or 21 E1 data
lines in an industry standard multiplexing format.
Each of the DS1 lines contain 24 timeslots of 64 or 56 kbps each, and each of the E1 lines contain 32
timeslots of 64 or 56 kbps each. The DS1and E1 lines can support one or more user data channels which
appear to the system as serial interfaces. Each serial interface is assigned one or more of the timeslots
giving the serial interface a bandwidth of n x 56 kbps or n x 64 kbps, where n is the number of timeslots
assigned. Any unused timeslots of the lines are filled with an idle channel pattern.
Unchannelized DS3 Overview
In the unchannelized mode of operation, a DS3 link provides a single high speed user data channel,
rather than being multiplexed into 28 DS1 or 21 E1 lines. The data channel appears to the system as a
serial interface that may be configured to use the full DS3 bandwidth or a smaller portion of the DS3
bandwidth.
In unchannelized DS3 mode, the OSM-12CT3/T1 supports the maintenance data link (MDL) channel
when using c-bit parity framing as well as local and network loopbacks.
Supported Features
The 12-port channelized/unchannelized DS3 OSMs support the following features:
•
General Features, page 7-3
•
Serial Encapsulation Protocols, page 7-3
•
DSU Mode, page 7-4
•
T1 Configuration Options, page 7-4
•
E1 Configuration Options, page 7-4
•
DS3 Alarms, page 7-5
•
Network Management, page 7-5
•
Quality of Service Protocols, page 7-5
Link Type
Cost
DS3
336
Unframed E1
16
1-6 DS-/TS
4
7-9 DS0/TS
6
10-16 DS0/TS
8
17-24 DS0/TS
12
25-31 TS
16
