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Researchers Test WiFi Access From Moving Vehicles
Julie188 writes "Researchers from Microsoft and the University of Massachusetts have been working on a technology that would let mobile phones and other 3G devices automatically switch to public WiFi even while the device is traveling in a vehicle. The technology is dubbed Wiffler and earlier this year its creators took it for a test drive with some interesting results. Although the researchers determined that a reliable public WiFi hotspot would be available to their test vehicles only 11% of the time, the Wiffler protocol was able to offload almost 50% of the data from 3G to WiFi."
I prefer the OSS term for this technology, "autoleech".
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
The multipath and doppler effects SUCK. This is why Wimax doesn't work well in vehicles and why the Mobile Wimax variant is more popular in such realms.
But once you have the physical layer taken care of, you can play cool little tricks like data queuing for WAPs to save cost. Locational awareness is also feasible to anticipate whether there will be a hotspot in a quarter of a mile or to go ahead with the transfer now.
When I hit one of these, it sort of grinds everything to a halt, as the phone thinks it has a wi-fi connection but does not.
San Francisco Photographers
There's been a fair number of stories recently of people getting in trouble for "stealing" bandwidth from unsecured wireless routers, and not just when using it for illegal purposes. I don't agree with this. I think it should be the owners responsibility to secure their network, but the possibility for legal ramifications exists.
"Always forgive your enemies; nothing annoys them so much." - Oscar Wilde
Just because it doesn't work on your iFruit doesn't mean that it won't work with something that was designed for this purpose.
But how would a city bus line offering Wi-Fi negotiate carriage with every AP on its routes?
... researchers determined that a reliable public WiFi hotspot would be available to their test vehicles only 11% of the time ...
but then a closer look found that in those cases, 99% had the SID "Free Public WiFi".
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
But how would a city bus line offering Wi-Fi negotiate carriage with every AP on its routes?
And would a bus using this technology in the Netherlands have to register as an ISP?
You need this, a box which eliminates doppler and multipath from 802.11 channels.
It's already been done in 2007 by Nokia and Siemens, and is part of the 3GPP standard. 3GPP TR 23.806 (for voice, but works for data too). Repeat after me all you Americans: International standards are better than propriatary ones.
I certainly hope so, because that will help overturn the rules that imply same for hotels. It simply doesn't make sense; if it has to be regulated, it could just as easily be changed to "a hotel has to register as an ISP if it provides network access to others than their guests". It's besides the point though, as far as TFA is concerned. However, trains already provide Wi-Fi as we speak and buses may just as well - and they'll have a harder time convincing the powers that be that they're not serving the public. It will be nigh impossible to restrict access to people inside the bus, unless you feel like changing the passkey for the connection every you hop onto a bus.
The transit system around here was working on that for a while. What they did was set up a low power access point in the middle of the bus, and hooked that up to a cellular card. The effect was that you were using WiFi, but since you were in the same reference frame, you didn't have to deal with any of the random interruptions you would otherwise have to deal with.
The main problem would be in tunnels and plain old congestion.
Isn't this idea kind of what the 802.11p amendment that was published last summer was for?
with the typical AP having only a 300m range in open air and traveling at 55+ MPH, they would be in and out of the AP quite quickly. But, if they were sitting in traffic then that would be another story. I've been quite disappointed with how many of the Android apps rely on 100% data connectivity instead of intermittent connectivity. Even the facebook app just dumps a notification and does not continue with the post or upload unless the user interacts with the notification. I found no setting in the maps/navigation app to cache the route but must rely on me manually scrolling through the entire route to cache it and then hit the road. Believe it or not, there are still dead xG spots out there and wifi-only is currently not an option.
Maybe this study will wake up the apps developers to intermittent connectivity and make the device much easier to use.
LoB
"Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
Isn't that what HIP is for? Maintaining identity/virtual connections as one transitions across multiple Internet access points? At first glance, this appears to be reinventing the wheel.
Here's a paper written by a fellow who's now a professor at U of I, Chicago which relates to the topic. The gist is that taxi's in a city were equipped with wifi and opportunistically connected to open access points as they traveled. The article won't revolutionize anything but it's certainly an interesting read and something worthy of building upon. One of the interesting parts is that the taxi-side wifi used a custom written utility to accelerate establishing a connection which didn't bother negotiating transmission speed but rather used a fixed 11Mbps as this was determined to be optimal for the setting.
It will be nigh impossible to restrict access to people inside the bus, unless you feel like changing the passkey for the connection every you hop onto a bus.
Or unless the captive portal requires logging in with credentials issued by the transit authority. For example, even a bus system that doesn't operate on Sundays issues reduced-fare cards to seniors and people with disabilities, and it also sells monthly passes.