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
.
Revision 1.5
Copyright © 2007 BlueTree Wireless Data Inc. Page 26 of 67
