Thursday, February 5, 2009

Minneapolis Wi-Fi network aids rescuers - bridge collapse

So the real question is when are ARES/RACES groups going to realize its time to implement this using products like the Ubiquiti NS3/XR3 on 3 GHz, the lower half (2.3 GHz) of the 2.4 GHz ham band, the 5.8 GHz band, or even 900 MHz with something like the XR9.

Ubiquiti's AirOS firmware as well as popular third party firmware such as DD-WRT all now have mesh networking protocols like WDS (Wireless Distribution System) built in.

Mesh protocols are designed for self-healing networks that are able to load balance WAN (wide area network) access. They also combine some of the ideas contained in the Radio Shortest Path First protocol. If the you are not up to par on the dynamics of mesh networks, here are a few links: An ad hoc wireless mesh routing daemon
You may also wish to read the article by John, K8OCL, titled "New High-Speed Multi-Media Radio Mesh Networking," printed in the Fall 2008 CQ-VHF magazine.

Mesh is very powerful stuff. And when you throw SIP / Asterisk based telephony on top of it, you have an instant voice system. Just plug in an IP phone or analog telephone adapter. Now not only can you exchange large image files, email, word-processing and other files that emergency responders and served agencies find invaluable. You can also pick up a phone or (seamlessly) bridge existing ones that are dead due to a land-line failure... etc.


Emergency communications offer the greatest opportunity for Radio Local Area Network (RLAN) technology to excel and for amateurs to push the envelope in the public service sector, using this technology....

Another good read is the Winter 2005 issue of CQ-VHF. John, K8OCL wrote a HSMM column on a HSMM portable setup for EmComm organizations.


Anonymous said...

OK, Steve.

In the interest of perhaps getting a conversation going, I'll leave a comment. In spite of the fact that I can talk to you just about any time.

As you know, I have been talking about this kind of thing for a while. I used to beat the drum for a large permanent packet network, but after dealing with the Wisconsin network for quite some time, and learning of all of the problems inherent in such a network, it soon became clear that such a proposition was just not practical.

There is a crying need for hams to supplement the internet, and to replace access points when natural events cause spot outages. The internet as a whole is very robust. We should not try and replace it. While Win-Link and conventional packet have their place, an ad-hoc mesh network is far more useful in times of emergency.

Over the course of the last 20 years, I have operated in a ton of emergency drills and have spent 15 years as a Skywarn net control. I've watched communications evolve from basic telephone, fax and radio to E-Mail and beyond. Hams cannot expect to be useful in this evolving environment with the same old tools.

We need to be able to jump in and furnish an access point where there is none, due to an underdeveloped internet access system, or disaster-induced failures. We need to leverage the internet rather than try and replace it with our own inadequate system. As you have pointed out, the technolgy is there and can be harnessed for real good work.

I believe that ARES and other emergency operating entities need to focus on developing rapid-response ad-hoc networking skills so that we can do what we claim to be capable of. Otherwise, we'll only be relevant in third-world nations that get hit by hurricanes.

There are many rural areas in this country that are only served by dial-up internet access. The heavy flow of emergency-related traffic will bring forth a demand for quickly-implemented wireless broadband. Hams can be in a position to furnish this as we do have radio experience.

In short, it's time to get to work.

Thanks for a good article.

kb9aln said...


I am dumb. Forgot to fill in the blanks and identify myself. That last comment was mine.

kb9mwr said...

Thanks for your comments Andy,

Just to clarify, I think a lot hams only see this type of thing for distributing internet. That of course isn't my interest.

There are so many free / open source Linux based packages like the phpbb message board, asterisk and its "meetme" conference room and so forth... Hams can create a more useful (due to the speed) amprnet or internal network (intranet) like we had with 9k6, but much less painstakingly slow.

Useful world wide web sites can be mirrored with wget, etc. Wormhole virtual tunnels ( much like what we did over normal packet to initially interconnect, detached RF networks etc.

A quick glance on the word wide web seems to show there are probably more hams active on the internet than on the radio.

Perhaps if we didn't have our head up our butt long ago we could have created an amprnet / Hinternet where all these hammy types of discussions and coding projects can take place. Its never to late to do something 21st century useful....