Ohio Amateur Radio TCP/IP Address Assignment

Obtaining an IP address in the Ohio Amateur Radio Network

These pages and links walk you through the process to get an address to use with amateur radio TCP/IP software in the state of Ohio. For more information about TCP/IP, look at IntroNOS: An Introduction to Amateur Radio TCP/IP. TNOS is a popular version of the KA9Q software; it's available for both MS-DOS and Unix.

This page exists because the IP addresses that ham TCP/IP stations use need to be coordinated, and, and the Miami Valley FM Association manages the address assignments for Ohio.

An Important Note

As noted in more detail below, you don't need an "official" assigned address to experiment with TCP/IP on ham radio. If you are not connecting to other ham TCP/IP stations (and conversely, if they're not connecting to you), either via RF routers or an Internet gateway, the address you're using doesn't matter, since no one other than you (or your local group) can get to you.

In that case, you can simply use one of the blocks of "unrouteable" IP addresses. There are several of these assigned under an Internet specification document called "RFC 1918":

In addition, we have set aside the 44.71.63.x subnet in the Ohio plan for experimental and unrouted use.

So, unless you are building an AXIP internet gateway, or a routed RF network, please use address in these nets rather than asking for an assigned address or subnet.

Finally, just to avoid confusion -- you cannot use an address in the amprnet (44.x.x.x) space to connect to the Internet. The amprnet is not "routable" which means that other computers directly connected to the Internet cannot send their packets to an amprnet address; if they see an amprnet address, they simply won't know what to do with it. amprnet addresses can only be used by amateur stations on an RF network, and can only be used across the Internet when they are encapsulated via an AXIP Internet gateway that routes to other ham RF networks.

(It is possible to send email to a callsign@ampr.org address via the Internet; that uses something called MX records and requires an entry in the ampr.org nameserver database, but not an amprnet IP address. If you're interested in doing this, please contact me for further details.)

How are addresses assigned?

The Ohio network is based on the concept of delegated authority. Each LAN -- a Local Area Network that consists of a more-or-less permanent group of stations that can all work each other directly on the same frequency and baud rate -- is assigned a block of addresses. Individual addresses are assigned within the local group.

So, if you're getting started with TCP/IP, you should check the Assigned LANs to see if there's already a LAN in your area. If there is, contact the listed contact person to learn more about the LAN and to obtain an address.

If there isn't an existing LAN for your area, you need to ask this question:

Do you need an assigned address?

If you're just beginning to explore NOS, and are working alone, or with a buddy or two, you probably don't need -- and shouldn't request -- an "official" address. IP addresses are assigned and coordinated because they are used to route packets from one place to another, but if you are don't link up with the outside world, you can pick whatever addresses you'd like as long as all the folks in the local group agree on who uses what.

In fact, we've set aside one of the Ohio subnets for that purpose -- addresses in the range from through are available for experimental and uncoordinated use. We strongly encourage you to use these addresses while you're getting your feet wet.

If you reach the point where you want to create a permanent LAN for your area, you should read the Setting up a New LAN page and follow the instructions there. You can then switch from the experimental address block to your own subnet of addresses.

And, if you'd like an assigned address even though you don't connect to any other part of the network, we'll issue one. But please remember that well over half the assigned addresses in the old Ohio scheme were never activated, and it's easier for everyone if we don't use up the address space unnecessarily. To request an address, send an email (using the icon below) that includes: your name, callsign, packet and/or email addresses, city and county, and the hostname you'd like (if you don't specify it will be callsign@ampr.org).