Overview Internet TCP/IP Connection via Cdpd

AirLink Application Notes

1. Overview

This document describes how to connect the AirLink Raven CDPD Modem to the IP5200 Async- Router from Data Communications for Business (DCB). Information on the IP5200 and DCB is available at www.dcbnet.com. Additional information about AirLink Communications products is available at www.AirLink.com

2. Internet (TCP/IP) Connection via CDPD

Normally, remote access to an IP 5200 is done via Dialup Telephone Line. When using CDPD, remote access to is done via a TCP/IP connection to the CDPD Network (ie: Internet) and the use of a CDPD Modem connected to a DCBNet IP5200 Single-Port Async-Router.

On the HOST side, access to the CDPD Network could be made using any of the following means:

1.Using a Frame Relay connection into the CDPD Network

2.Using the public Internet

3.Using another CDPD Modem connected to the Host System

Frame	Internet	Other
Relay	Internet	CDPD
		Networks
1	2
	2
	Local
3	CDPD
	Network

3. Ethernet Device & IP5200 Cabling & Installation

Setting up the Ethernet device (PC, RTU, PLC, etc) for communicating over CDPD is fairly straightforward. All the same configuration settings used for a LAN installation apply to a CDPD installation. Since the device is actually sitting on a very small LAN, (just the device and the IP5200), the IP Address would be a private IP, such as: 192.168.1.101. The IP5200 would have an Address in the same range, such as: 192.168.1.100.

DNS, FTP, SMTP, and Email settings would be for servers visible to the public Internet or in the case of Frame Relay connections to the CDPD network – IP Addresses visible to the Frame Relay cloud. (See your Network Administrator or Carrier for more details on which Addresses or server names to use).

When the device initiates Ethernet traffic (by either sending an email or starting an FTP session, etc), the router will dial the CDPD modem and establish a PPP connection. The CDPD Modem will supply the router with its IP address, virtually becoming the router’s Internet Service Provider (ISP).

AirLink Communications

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