Installation guide

LMU Users Guide

V1.0.6 December 10 2009

- 110 - CalAmp Proprietary & Confidential

14.1.4.4 Configuring the LMU for Dial-Up Networking

When a user is connected to any device that supports Dial-Up Networking, they are

generally concerned about one thing, speed. Unfortunately in this case they are using iDEN

devices, so the maximum thru-put that can be expected is around 10kbps. For this reason we

are going to want to block as much traffic as possible using the Remote Host IP Address list.

Specifically we want to limit access to just the servers at our office and the servers at our

data center. The IP range used by the office is 166.143.185.65 thru 166.143.185.90 and the

IP range used by the data hosting facility is 172.90.80.240 thru 172.90.81.50

To set up an appropriate access list we would use the following commands:

AT$APP PARAM 1282,0,166.143.185.255

AT$APP PARAM 1282,1,172.90.255.255

It is also common for users to up the host port baud and modem port rate of the LMU

when using dial-up networking. In this case, however, there is really no point. Both the

iDEN modem port speed (38 400 bps) and the default host port speeds (115 200 bps) well

exceed the maximum throughput of the wireless network (~10 000bps).

The last thing we want to deal with is preventing any automatic resets of the LMU’s wireless

modem. If a reset of the modem occurs, the Dial-Up networking session with a host device

(laptop or PDA) also resets thus making for a poor user experience.

Looking back at the Working with Comm section we find the following points for automatic

resets:

• Send Fail Restart

• Log Activity Restart

• Connection Monitoring

• Querying for Network Status

On the iDEN side, the Query for Network Status doesn’t exist and can thus be ignored,

however, the other three should be turned off.

To turn off the Send Fail Restart you would use:

ATS149=0

To turn off the Log Activity Restart you would use:

ATS157=0

And lastly to turn off the Connection Monitor, you would use two commands:

ATS152=0

AT$APP PARAM 1024,34,8,8

With the exception of the PULS address, these IPs were chosen at random.