User`s guide

4000 & 5000 Series User’s Guide

5.2 Dial-up Networking (DUN) over serial

 Regardless of the modem type, using a serial cable will cap the

bandwidth at 115200 kbps. For owners of EV-DO modems (4600/A

& 5600/A), the serial port will be a bottleneck in terms of

performance, as it will reduce the data throughput to approximately

5% of its maximum potential, and even less for EV-DO Rev. A

modems. Whenever possible, use an Ethernet or USB connection to

take full advantage of throughput.

Some terminals do not have RJ45 Ethernet or USB connectors and require using

a DB9 RS232 standard serial connector to interface with the modem. This

section covers programmable devices such as PC or smart (programmable)

machinery.

• If the attached device is not programmable, then you cannot do

DUN, and will have to use the Serial IP feature to communicate with

the device. Refer to Section 7: Serial IP for details.

• If the modem will be used with a programmable device that can

make PPP connections, then refer to that device's documentation to

create the dial-up session. The phone number to dial will be #777.

• If the modem will be used with a PC, then the user must install a

standard modem driver on the COM port to which the modem is

physically connected, and then create a dial-up connection running

on that driver. This dial-up connection will dial the modem so that a

PPP session is established between modem and PC. Meanwhile, the

modem will make a PPP session of its own to connect to the network.

For a walkthrough on creating a DUN connection in Windows, refer to

Appendix D.