The COM/IP solution for communicating with meters using wireless network connections

AMR applications have successfully used modem connections for many years. Though a modem connection can provide reliable communications, a modem and telephone line are required at both ends. Wireless data network services may provide an attractive alternative.

The Problem

The AMR application issues AT modem commands to dial modem calls, but the wireless network service is accessed via TCP/IP and the wireless endpoints have an IP address (not a telephone number).

The COM/IP Solution

The COM/IP Redirector provides software modems (that behave like physical modems) and converts the application's modem commands and serial data stream to a TCP/IP connection. The AMR application continues to use AT commands to dial, and COM/IP makes the connection to the TCP/IP destination.

The COM/IP Redirector is installed on the AMR application server and is configured to create as many virtual COM ports as the AMR application can use at one time.

The AMR application is reconfigured to use COM/IP virtual COM ports instead of the local COM ports that formerly provided modems.

Each time an AMR application opens a virtual COM port:

1. The COM/IP Redirector provides a software modem that processes AT commands as a Hayes-compatible modem.
2. When the AMR application uses the ATD command to dial, it dials an IP address instead of a telephone number. If dynamic IP addressing is required, the application can dial a telephone number that COM/IP translates to a hostname and submits to DNS to obtain the IP address.
3. The COM/IP Redirector then makes a TCP/IP connection to the indicated TCP/IP destination, which is reached by the wireless network service provider.

Key Advantages of the COM/IP Solution

• The AMR application no longer needs physical modems and their telephone lines.
• The AMR application does not change. It can use wireless network services even though it continues to employ AT modem commands.
• The AMR system may transition over a period of time from modem communication to wireless by simply using the COM/IP virtual COM ports as the end points convert to wireless access.