Operation - ADTRAN Total Access OC-3 L3 Installation And Maintenance Practice

Auto-Provisioning will not overwrite Linked Provi-
sioning settings received on installation. All subsequent
provisioning changes are made through the SCU
communications link.

3. OPERATION

The OC-3 MUX is a common module that serves as an
OC-3 interface to the shelf and provides for the multi-
plexing/demultiplexing of two DS3s and 28 DS1s to/
from the OC-3 signal. Each access module contains the
interfaces and the appropriate circuitry to interface with
the local loop.
The OC-3 MUX interfaces with a standard OC-3 signal
from the network and provides logic-level signals to the
access modules from one of the three STS-1s of the
OC-3, which is groomed to the 28 DS1 channels. The
remaining two STS-1s of OC-3 signal are converted
into standard DS3 signals and returned to the network
through the 75 Ω Quad BNC interface provided on the
backplane. The STS-1 path must carry DS3 contents,
and the card does not support VT mapping format.
NOTE
Transmit and receive ports of a DS3 interface
not connected to a network should be disabled
by unmapping it from an STS-1.
An STS-1 Mapper on the OC-3 MUX routes, as provi-
sioned, two STS-1s of the OC-3 signal to the DS3
standard electrical interfaces. The STS-1 Mapper routes
the third provisioned STS-1 to the STS-1/DS1 (M13)
multiplexer/demultiplexer module located in the OC-3
MUX module. The STS-1 path terminated or originated
by this STS-1/DS1 (M13) multiplexer/demultiplexer
access module will be referenced hereafter in this
document as DS1 Drops.
The OC-3 MUX will occupy either one or both of the
multiplexer slots of the Total Access 3000/3010 chassis.
In the dual configuration, the OC-3 MUXs will operate
in a 1+1 relationship protection mode.
OC-3/Network Interface
Physical connection to the network interface is via dual
SC connectors on the OC-3 MUX. Signal specifications
are as follows:
• Fiber Type:
• Wavelength:
• Optical Budget:
• Transmit Level:
4
Single mode
1310 nm
13 dB (minimum)
−8 to −15 dBm
• Receive Level:
• Optics:
DS3/Network Interface
Physical connections to the network interface are made
on the Total Access backplane using two transmit/
receiver pairs of 75 Ω BNC connectors.
Subtending Two Total Access 3000/3010
Shelves
The OC-3 MUX terminates one STS-1 path to the shelf
in which it is installed. The other two STS-1 paths
contained within the OC-3 may be provided to two
additional shelves via the optional Quad BNC module
(P/N 1181007L1 or L2) that connects to the backplane
of the Total Access 3000/3010. Each subtended shelf
must contain a DS3 MUX and an appropriate SCU. The
subtended shelves accept the DS3 signal via an optional
Dual BNC module (P/N 1181004L1). The RS-485
configuration is recommended for connecting
subtended shelves in a "cluster topology."
NOTE
When implementing this configuration, the
shelf that contains the OC-3 MUX must be
equipped with an SCU configured as the
"HOST" for the chain, and each subtended
shelf must be equipped with SCUs configured
as a "Client."
This configuration provides for a host/client or master/
slave relationship between the shelves, with the shelf
holding the host SCU being the host or master. Commu-
nication between shelves is via the RS-485 bus.
Power Interface
The Total Access 3000/3010 backplane delivers
−48 VDC to the OC-3 MUX.
External Clock Interfaces
External clock interfaces to the OC-3 MUX are via
wire-wrap pins on the Total Access 3000/3010 chassis
backplane.
User/Supervisory Interface
Access to the OC-3 MUX is through the SCU, which
provides a VT100 interface for a craft terminal.
Provisioning
All provisioning takes place through the SCU commu-
nication link. Onboard switches or jumpers are not
−8 to −28 dBm
Intermediate reach
61181031L3-5A