Stand-Alone Mwr 1941-Dc; Configuring The Link Noise Monitor - Cisco MWR 1941-DC - 1941 Mobile Wireless Router Software Configuration Manual

Chapter 4 Configuring the MWR 1941-DC in an IP-RAN
To verify the status of the relays on an MWR 1941-DC router, use the show controllers command.

Stand-Alone MWR 1941-DC

The MWR 1941-DC router has relays that work with a special "y" cable for redundancy and are
controlled by HSRP. You can, however, use the MWR 1941-DC as a stand-alone device. If you choose
not to use the MWR 1941-DC in a redundant configuration, you should not configure HSRP and you
must control the relays of the VWIC card manually.
To manually set the relays to open or closed, do the following starting in global configuration mode:
Enter redundancy mode.
Step 1
Router(config)# redundancy
Step 2 Enter the y-cable mode.
Router(config-r)# mode y-cable
Specify that the router is to be used as a stand-alone device. This command closes the relays.
Step 3
Router(config-r-y)# standalone
Exit y-mode configuration mode.
Step 4
Router(config-r-y)# exit
To verify the status of the relays on an MWR 1941-DC router, use the show controllers command.

Configuring the Link Noise Monitor

This feature requires Cisco IOS Release 12.2(8)MC2d and later be installed on the MWR 1941-DC
Note
router.
Noise on T1 and E1 links that span between the BTS and central office can affect voice quality for mobile
users to the point where it becomes unacceptable. To monitor the quality of individual links in a multilink
bundle, you can configure the Link Noise Monitor (LNM) on your MWR 1941-DC router
The LNM detects, alerts, and removes noisy links from a bundle based on user-defined thresholds and
durations. In addition, the LNM notifies the operator once the quality of the line has improved, and
restores the link service if the link has been removed.
Specifically, to detect noise on a link, the LNM monitors the following two types of errors which make
up the Bit Error Rate (BER) and compares the number of errors with the user-defined thresholds:
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Line Code Violation (LCV)—A Bi-Polar Violation (BPV) or Excessive Zeroes (EXZ) error has
occurred.
Path Code Violation (PCV)—A Cyclic Redundancy Check (CRC) error, which is generally caused
by one or more LCV or logic errors, has occurred in a time slot.
Cisco MWR 1941-DC Mobile Wireless Edge Router Software Configuration Guide
Configuring the Link Noise Monitor
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