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4-9
PA-MC-T3-EC Port Adapter Installation and Configuration
OL-10589-02
Chapter 4 Configuring the Unchannelized Mode
Configuring an Unchannelized T3 Link
Caution
The PA-MC-T3-EC does not support the Kentrox DSU bandwidth setting of 1.0 mbps. The Kentrox DSU
speed must be set to 1.5 mbps or greater.
Caution
For all DSU modes, the DSU must be configured for the same transmit and receive speeds. Asymmetrical
transmit and receive speeds are not supported.
Setting the Bandwidth for the Serial Interface
In interface configuration mode, set the bandwidth to be used by the serial interface on the T3 link by
entering the
dsu bandwidth
bandwidth
configuration command, as in the following example:
Router(config-if)#
dsu bandwidth 16000
The allowable bandwidth range is 1 to 44210 kbps. Use the
no
form of this command to return to the
default, 44210.
The local DSU bandwidth value must match the remote DSU or T3 port bandwidth exactly. For example,
if you set the DSU bandwidth to 16000 on the local port, you must do the same on the remote DSU or
T3 port.
Setting Scrambling for the Serial Interface
In interface configuration mode, enable serial interface scrambling by entering the
scramble
configuration command, as in the following example:
Router(config-if)#
scramble
Use the
no
form of this command to restore the default value, disabled.
The local port configuration must match the remote DSU or T3 port configuration. For example, if you
enable scrambling on the local port, you must do the same on the remote DSU or T3 port.
Configuring Loopback Mode for the Serial Interface
With loopbacks, you can detect and isolate equipment malfunctions by testing the connection between
the
PA-MC-T3-EC interface and a remote device such as a CSU/DSU. Remote loopback sends a
command to loop the T3 line at the far end. It can be used to diagnose problems with cables from the
port adapter to the switching office. Network loopback loops the PA-MC-T3-EC T3 port back to the
network, allowing the remote end to test the connection to the PA-MC-T3-EC.
Local loopback loops the PA-MC-T3-EC T3 port back to itself, allowing it to be tested in isolation from
the T3 cables and remote T3 equipment.
The
loopback
command places an interface in loopback mode, which enables test packets that are
generated from the
ping
command to loop through a remote device and cables. If the packets complete
the loop, the connection is good. If not, you can isolate a fault to the remote device or cables in the path
of the loopback test.
You can configure the serial interface for loopback modes using the
loopback
[
local | network
|
remote
]
interface command.
The default is no loopback.
To return the serial interface to its default unlooped condition, use the
no
form of the command.