1-3
Clear Channel 6-Port T3 (DS3) Line Card Installation and Configuration
OL-3449-02
Chapter1 Overview Interoperability Guidelines for 6T3 Line Card DSUs
Interoperability Guidelines for 6T3 Line Card DSUs
The 6T3 line card supports several types of integrated data service units (DSUs). Ta ble 1-1 lists the
feature compatibilities of 6T3 line card DSUs.

Maintenance Data Link Messages

T3 maintenance data link (MDL) messages are used to communicate identification information between
local and remote ports. The type of information included in MDL messages inc ludes the eq uipm ent
identification code (EIC), location identification code (LIC) , f rame iden tification code (FIC), unit, Path
Facility Identification (PFI), port number, and Genera tor Ide nti ficatio n num be rs. The values for ea ch
piece of MDL message identification can be defined only by a network admini st rator and are discussed
in ANSI T1.107.
For information on transporting MDL messages between source and destination T3 ports on a Ci sco
7304 router, refer to T3 Maintenance Data Link Messages on the Cisco 7304 Router.
LEDs
The 6-port 6T3 line card has six LNK LEDs, one for each port, as well as one OIR LED and one
STATUS LED. (See Figure 1-2.)
Figure 1-2 LEDs on th e 6T3 Line Card
After system initialization, the STAT US LED goes on to indicate that power is received and that the
6T3 line card is enabled for operation.
Table1-1 Feature Compatibilitie s of 6T3 Line Card DSUs
DSU Full Rate
Support Scrambling
Support Subrate
Support MDL1 Support
Adtran Yes No Yes No
DL3100 Yes Yes Yes No
Kentrox Yes Ye s2Yes 2No
Larscom Yes Yes Yes No
1. MDL (Maintenance Data Link)
2. The 6T3 line card supports scrambling and Kentrox subrate at the same time.
TX
LNK
RX
0
66771
7300-6T3
6-PORT T3 DSU
STATUS
OIR
TX
LNK
RX
1TX
LNK
RX
2TX
LNK
RX
3TX
LNK
RX
4TX
LNK
RX
5