Sunday, January 24, 2010

Wondering about AMPRnet

Do you know about AMPRnet? I've wondered about this mythical network off and on since the 1980's packet boom. Back then, I was doing 1200 bps 2-meter packet from my home in Guilford, CT. I had a nice little setup with a toaster-style Macintosh, a KAM+, and a 10-20 Watt transmitter (Handytalky with an amp.). It would do the usual packet thing -- access local BBSs, digipeaters, etc. With a lot of effort, I could connect through RF gateways into New York or the Boston area. It was kind of fun sitting there and listening to each packet going out and (hopefully) returning. Not useful, by any means, but entertaining.

Then I got the TCP/IP bug. On the one hand, this was a loser for performance, adding all the overhead of full routing to each packet. On the other hand, there was a degree of error control, and I had actual IP addresses assigned to me! I was ( and ( So far as I know, the IPs are still "mine", but the server has forgotten about me. :-(

There is a "Class A" network assignment for AMPRnet or "" --, or as we now say in CIDR terms, 44/8. That's a big deal. That is an allocation of 2**24 = 16,777,216 individual IP addresses, about 1/256 of the entire IPv4 address space, assigned to Amateur Radio. That's the same IPv4 address space that is supposed to be exhausted as soon as 2011.

AMPRnet appears to be very lightly administered (and that's being polite) -- even for an amateur radio activity. The allocations are supposed to be managed by regional volunteers, but coverage seems spotty. The advertised coordinator for my area seems to be inactive now, so there is no one for me to even ask about my allocation! And, if you can get a number, it doesn't have much value, since no one can route packets to you unless you make "upstream" arrangements that are impractical for individuals. People seem to set up tunnels to a server at, which probably works, but is hardly the way to build a big network!

Traditional packet radio has been in long decline, except for special uses like APRS and DX spotting. Newer digital developments, such as DSTAR and HSMM use TCP/IP technology, since it's still the standard for computer networking, and they may use AMPRnet addresses.

What about that 44/8 network? Is there any way, other than history, to justify maintaining that huge allocation in the face of a global IPv4 number shortage? I know of no simple way to find out which ones are allocated. I would be surprised if there were as many as 1,000 in use. Out of 16 million, it's a trivial number.

The simple fact is that amateurs got a Class A allocation in 1992, when people weren't asking many questions and commercial use of the Internet was just beginning. We'd never get it today.

We should ask why amateurs actually want any IP number assignments. Wouldn't we do just as well with a non-routable private network like 10/8? The vision that somehow a random Internet user needs to interact with a random Amateur Radio station is an odd one. If it involves RF transmission, only licensed operators are allowed -- although the status of server based systems like e-mail and the web may be unclear. It's 2010, and we have 20 years of Internet and ham radio development to look back on. Ham digital nets are fragmented and don't talk to each other much, let alone the Internet as a whole. Why do we need full routability between the RF world and the Internet?

The Internet <--> ham model that is working is tunneling through the Internet to interconnect radio devices and computers. Echolink, IRLP, and DSTAR rely on this mode. No permanent addresses are required. An RF-to-Internet gateway is generally at someone's house or place of work, where there is a standard Internet Service Provider connection. The gateway relies on the ISP's assigned address, just as we all do for domestic service.

So maybe AMPRnet needs to be put to rest, giving its water back to the tribe. That would make a nice press release: Public-spirited amateur radio operators help the Internet put off catastrophe for 2 months!

Or, maybe I'm missing something important. Let me know in the comments!

Jeff, WA4ZKO, has some good comments here and here.

Thursday, January 14, 2010

Volunteering at League HQ

Here's the scene at the ARRL Headquarters lobby, as seen from the volunteer Tour Guides' nook. We are a lot busier today than normal, because of various committee meetings and other activities around the Board meeting this weekend.

I've been a ham (amateur radio operator) now for 52 years, enjoying many facets of the hobby -- from Morse Code ("CW") to Open Source Software. In the past year, I've been volunteering at ARRL HQ, as a Tour Guide.

Tour Guides are an interesting lot. They are generally retired folk, like me, who have a bit of time available and who have a long involvement in the hobby and a commitment to the League. I see most of them only rarely, since our slots don't overlap. (I have Thursday mornings, if you'd like to drop in.) The League's coordinator, Diane Petrilli, does know how to keep us motivated, with an occasional group lunch, and a certain amount of "swag". Along these lines, one the best benefits is a special discount at the ARRL bookstore.

The real reason to be a Tour Guide, for me, is to meet a very interesting cross section of radio amateurs, along with spouses, friends, and family members. These are mostly "drop ins" who are visiting in the Newington CT area. Generally, they are long-time hams and League Members. Some of them are quite capable of giving me the tour -- and are happy to do so! On the other hand, there are a few who are just getting interested in the hobby and who need some encouragement which I'm happy to provide.

Tour Guides provide an interface between the visiting public and the ARRL organization, so the flip side for us is having the chance to learn what's what at the League itself. Many hams, myself included, have grown up thinking of the ARRL Headquarters as something like the "mother church". The first visit here is like a pilgrimage to hallowed ground, the historic station W1AW, the editorial offices of the publications like QST, and home of many services for members. I haven't seen anyone kneel to kiss the ground yet, but you get the idea.

Another good reason to hang out at HQ is the chance to operate W1AW. It's a thrill to be a "rare one" on the amateur shortwave bands. It's easy to create a "pile-up" of operators wanting to talk to this classic station. Just as interesting is the chance to use your choice of state-of-the-art radio equipment. It's one of the few ways to "try before you buy".

Today, with the Board of Directors in town, there don't seem to be any normal visitors. A good time to meet some Directors, enjoy the Board's snacks and coffee, and pursue the Internet.