Ask Slashdot: Ad-Hoc Wireless Mesh Network For Emergency Vehicles?

First time accepted submitter Texaskilt writes "I am looking to put together a mobile mesh network for my volunteer fire department and would like some recommendations from the Slashdot crowd. Ideally, the network would consist of cheap wireless routers (Linksys WRT-type) mounted on each vehicle. From there, tablets or other wireless devices could connect to the router. When the vehicles are in the station, the routers would auto-connect to the WiFi network to receive calls for service and other updates. When out on a call, the router would form an ad-hoc network with other vehicles on the scene. If a vehicle came into range of an Internet 'hotspot,' it would notify other vehicles and become a gateway for the rest of the 'ad-hoc' networked vehicles. I've looked at Freifunk for this, but would like some other options. Recommendations please?"

Comments

Project Byzantium?

[Intrepid imaginaut]

http://project-byzantium.org/

I have to wonder though, what's wrong with good old fashioned radios.

Re:Project Byzantium?

[slimjim8094]

I am an emergency responder, and frankly I can't come up with much I'd use internet for. Medical history databases? Like what? Even at the hospital they need it sent from other hospitals if they don't already have it , there's no world-wide database of medical history, and even if there was can you imagine the nightmare of hooking every EMS agency up to it? And the security involved in handling patient data on such a scale? No thanks. In any case, it doesn't do me much good. Either the patient can tell me their medical history, or we've got much bigger problems. If they're unconscious, their history is secondary to keeping them alive, and you've got plenty to do on that front.

As for conferencing with doctors - that's crazy. We already have medical directors (physicians) we can call on the phone or over the radio, and it works fine when we need it. Plus, it won't give them any more information than what you can tell them over the phone anyway. I don't much want to fidget with Skype and a webcam when we're supposed to be deciding on a course of action. They can't interact with the patient anyway, and crappy wireless webcam video wouldn't be sufficient to notice something subtle that we missed.

The paramedics that I work with have CAD for tracking status, location, nature, etc - but they don't use it past dispatch. They can also send telemetry (specifically EKGs) from their monitors via their cellphones to the receiving hospital, so a heart attack can be diagnosed from the trace before we get there. That's pretty cool, but it's about the limit of what we've ever felt like we needed.

What is it for ?

[SomethingOrOther]

What is it for?

No really......
You have told us how you *think* you want to communicate, but not what information you are communicating.

The first step of any IT problem is to adapt your ideas to fit users needs........... not adapt users needs to fit your ideas.

Good ol' HAM radio?

[guruevi]

It works well, it won't give you much throughput but if all you need is some text and voice-based systems this should be plenty (it's about 300-9600 baud for IP so a slow serial link).

The issue I see with your approach is that when the vehicles are within range of each other they will also be within range of the same hotspot. So mesh is simply overkill. Mesh is intended for lots and lots of nodes in dense areas to connect to each other to a single (large?) uplink for either anonymizing or places where you cannot place (either due to economic or ecologic reasons) multiple antenna's. This works well for the GSM range because they are intended to cover literally miles (2W) at a frequency that is licensed to cooperate with each other and able to penetrate a lot of structures so two cell phones can technically talk to each other and extend the range of the original tower another mile or so (given the battery usage to do so is acceptable).

The 100 mW you get out of a WiFi router close to the hydrogen resonance frequency is simply not enough to cover a mile of random area which may have other compatible and incompatible broadband sources (microwaves, garage door openers, bluetooth ...) that could overpower the signal.

You're better off using the professional systems for this. WiMax base stations can be had for $1500 and a receiver is ~$200 and it will cover about 50km. Otherwise get a free cell phone plan for your volunteer fire department (I mean, some local corporate overlord MUST be benevolent enough) or set up your own transmitter (HAM or otherwise).

VANET

[ArhcAngel]

So you want to set up a VANET (Vehicular Ad-Hoc Network)...a subset of the MANET (mobile ad-hoc network). There's even a proposal for a secure fire truck communication protocol via VANET. Perhaps you can find more information by reaching out to some of the agencies working on this protocol.

Re:Get ready for it!

[HangingChad]

But when lives are on the line, a more conservative approach is called for.

You know nothing about being a first responder, especially out in rural areas where radio coverage may be spotty to non-existent.

Lives are on the line whether you have working comm or not. There were times I would have settled for two tin cans and a string if I could call for mutual aid on it. During emergencies ad-hoc networks could be a lifesaver.

There is a big need for self-discovering networking between emergency response vehicles. You won't find any commercial solutions in the budget of most departments.

Maybe drag your fat butt out and pull some volunteer shifts before you start telling people in the field what they need.

Re:easiest solution

[DarthBart]

My old department got hand-me-down trucks from the Texas Forest Service that we converted to brush trucks. We also got a 5000 gallon flight-line fuel truck from them that we converted to a mobile hydrant. The one "new" truck we bought, we bought as a used truck from a department in Chicago and had to take out a loan to pay for it. The bi-annual fundraising BBQ we held covered operating expenses, but that was just about it. Everything else came from handouts from the government.

The radio system? Patched together with stuff my dad & I bought at hamfests.

And there was more than a few times during the summer and we were fighting multihundred acre brush fires that I wish I knew exactly where each truck was, how much fuel and water they had onboard, and be able to set a waypoint for them to drive to for their next task.

That may not have all been able to have been done with an ad-hoc wireless system, but that would have helped immensely.