Zero Retries Guide to AREDN
Amateur Radio Emergency Data Network
Prelude to AREDN
There is a long history of repurposing “Part 15” (wireless devices designed for license-exempt operation under FCC Part 15.247 rules) into use in Amateur Radio. I credit the very first suggestion of this to Dewayne Hendricks WA8DZP. WA8DZP was the presenter of the Sunday Workshop at the 1996 ARRL and TAPR Digital Communications Conference titled “How to utilize Part 15 Radios for Ham Applications“. At that workshop, WA8DZP explained how Part 15 devices were rapidly evolving in industry (the first Wireless Local Area Networks) and even Internet access, and that perhaps Amateur Radio could adapt these mass-produced, reasonably priced devices for use in Amateur Radio activities and spectrum. Note that at the time of WA8DZP’s presentation, the IEEE 802.11 standard was not yet ratified, and none of the devices WA8DZP described followed any standard - they were all proprietary.
(I am indebted to WA8DZP - his presentation that morning changed my life by starting me down a path that eventually resulted in me becoming a writer, but that’s a story for another time.)
In the 25 years since WA8DZP’s observations, Amateur Radio adaptation of Part 15 devices has evolved. One of the most popular projects was Broadband Hamnet / High Speed Multimedia (HSMM) which used the (then) very popular Linksys WRT54 series of Wireless LAN routers, which had the rare ability to update their firmware to something other than what the manufacturer provided. For a while, it was popular to try to create Broadband Hamnet networks using WRT54 units. In the Seattle area, there was a variant of Broadband Hamnet that had additional capabilities, and we even had group meetings where you brought your WRT54 unit(s) to get help reflashing the firmware. In the end, the WRT54’s just didn’t have enough transmit power to effectively network over long distances and the 802.11b technology just wasn’t flexible enough. It was also the case that the noise floor on 2.4 GHz just became too great from too many wireless devices, especially (802.11b) 22 MHz channels that couldn’t be changed on the WRT54 units. From my observations, Broadband Hamnet / HSMM just seemed to gradually fade away.
It’s now 25 years later from WA8DZP’s observations and we now have AREDN, which implements WA8DZP’s vision by becoming mainstream in Amateur Radio.
Amateur Radio Emergency Data Network (AREDN) Overview
From AREDN Overview:
In today’s high-tech society people have become accustomed to different ways of handling their communication needs. The preferred methods involve short messaging and keyboard-to-keyboard communication, along with audio-video communication using Voice over IP (VoIP) and streaming technologies.
The amateur radio community is able to meet these high-bandwidth digital communication requirements by using FCC Part 97 amateur radio frequency bands to send digital data between devices which are linked with each other to form a self-healing, fault-tolerant data network. Some have described this as an amateur radio version of the Internet. Although it is not intended for connecting people to the Internet, an AREDN® mesh network will provide typical Internet or intranet-type applications to people who need to communicate across a wide area during an emergency or community event.
An AREDN® network is able to serve as the transport mechanism for the preferred applications people rely upon to communicate with each other in the normal course of their business and social interactions, including email, chat, phone service, document sharing, video conferencing, and many other useful programs. Depending on the characteristics of the AREDN® implementation, this digital data network can operate at near-Internet speeds with many miles between network nodes.
In my opinion, AREDN is an idea whose time has come in Amateur Radio. AREDN implements a high speed wireless network based on TCP/IP, AREDN has the same utility within Amateur Radio as Wi-Fi does to the general public. AREDN is not a substitute or supplement to commercial Internet Access, but rather it is a Intranet for Amateur Radio. AREDN can be used as a Wireless Local Area Network, a Wide Area Wireless Network, a Virtual Private Network (via Internet)… or all three simultaneously.
The primary attribute of AREDN is that it automatically forms a mesh network and hides most of the complexity of TCP/IP configuration, routing, and services and is largely plug and play. The AREDN developers have done a stellar job in hiding the complexities of wireless mesh networking. What little configuration is required is presented with a web page Graphical User Interface (GUI). Thus, AREDN is not only powerful and usable, but reasonably approachable by those who aren’t network professionals.
It’s the Applications, Not the Network
One critical mistake that Amateur Radio Operators often make, especially us techies, is that creating the system isn’t the same as a successful system. A system is essentially useless without users and applications. AREDN (and other networks) isn’t an exception to this basic truth. So what is AREDN useful for? Many of the same things that the Internet is useful for.
One primary thing that AREDN is
One of the
https://www.facebook.com/groups/aredn/
Orv Beach
October 18 at 6:53 PM ·
It's Linktober! "Meshoween" is coming 🙂
We've found that as networks grow both in node count and complexity, it's almost inevitable that they'll suffer from a packet storm eventually.
Now that the patch for mitigating those network packet storms has been rolled into an AREDN nightly build, we've decided that it's time to stress-test our network. On October 30th (starting at say, 9 a.m. local time) we'll attempt to link as many networks together to see how the network behaves. If you have a long-haul tunnel that you can bring up, feel free to do so.
HOWEVER, if you decide to participate in the test, or think you might be on a network that gets linked in, it's highly recommended that you update your node(s) to nightly build 571 or later to "inoculate" them against a possible incoming network storm.
Before October 30th, we'll provide a reminder and instructions on what to monitor during the test.
Thanks in advance for your consideration! Please pass this along to your AREDN network neighbors.
Orv W6BI
(on behalf of the AREDN dev team)
Orv Beach
October 6 at 1:36 PM ·
It's been about a month since we deployed a version of the AREDN software with a patch designed to mitigate network routing storms across the SoCal network. Developed by Tim KN6PLV, the patch is actually pretty benign; it just makes OLSR, the routing daemon, somewhat smarter about recognizing storms and suppressing them. Think of it as a vaccine for the network 🙂
Over the last month we gradually deployed it in most of the K6PVR nodes in Ventura County and western L.A. County, the K6ECG nodes on Mt. Wilson, and the K6BFG node on Magic Mountain. And Keith AI6BX has deployed it in about 10 nodes in and around the Inland Empire. As of this morning 40 nodes were running it and many of them are high-traffic nodes, which are the most effective places for the patched code to reside.
Absence of evidence is not evidence of absence, but since we deployed the patch the network has been quite stable. The network monitoring tool Tim developed now consistently fails to report any evidence of routing storms. Prior to pushing out the patch in SoCal we saw a couple. SFWEM (the San Francisco Wireless Emergency Mesh), which is a much more highly-meshed network than SoCal, saw many of them.
As a result of our positive outcomes while testing, the AREDN devs have merged KN6PLV's patch into the github repository. Expect it to show up in tomorrow's nightly build.
If you run a high-traffic node, or are in a highly-meshed network, I encourage you to use this nightly build. Your network will thank you
AREDN’s role in Popularizing Amateur Radio
AREDN Local Area Networking
AREDN Wide Area Networking