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Octal DS3/STS-1 I/O Front Module
Plexus 9000 Planning and Engineering Guide
Issue 4, March 26, 2004
Section 130-120-600
5-150
Telica,
Inc.
5.13.2
Functional Description
The Plexus 9000 accommodates up to 17 IOMs. The Octal DS-3 IOM can
terminate 8 DS-3s, which are equivalent to 224 DS-1s. These interfaces
support SS7 and ISDN protocols. The line side, which can terminate 8
DS-3, converts them to ATM cells and sends them to the SF module.
The Octal DS-3 IOM requires a Plexus 9000 chassis with a part number of
85-3004 or 85-3007. Octal DS-3 IOMs can be installed in physical slots
1-8, 11 and 14-21. The system’s ability to allow any line interface module
to occupy any I/O slot, along with the 1:N protection capability, prevents
the loss of valuable shelf space.
The system features 1:N protection of the DS-3 line interface modules.
The same front module type is used for both working and protection
applications, thus simplifying sparing, maintenance and inventory.
I/O-5 (physical slot 5) and I/O-13 (physical slot 17) are the DS-3
protection module slots and I/O-7 (physical slot 7) is the DS-1 protection
slot of the 85-3004 and 85-3007 chassis. I/O-5 protects I/O-1 to I/O-4 and
I/O-6 to I/O-8; I/O-13 protects I/O-9 to I/O-12 and I/O14 to I/O-17. If the
user does not desire to protect line- and trunk-side interfaces, the system
can be equipped with 17 interface modules.
The front Octal DS-3 IOMs require rear modules for physical interface
terminations. The associated rear modules feature two (2) BNC
connectors, transmit and receive, per DS-3 or STS-1 for a total of sixteen
connectors. The rear protection module does not have any connectors.
5.13.2.1
General Mechanical Representation
The Octal DS-3 IOM is approximately 14 inches high and plugs into the
midplane for connections to the rear IOM and to the SF and SP modules.
See
for an illustration of the midplane connector, the
DS3/STS-1 IOM and the front of the module. Labeling may differ
depending upon part number. Refer to
for a description of
the LEDS.