5 Cool Wireless Reseach Projects

Bob B writes "Including an effort by MIT researchers to exploit dense urban networks of existing Wi-Fi access points to create municipal wireless networks rather than relying on EarthLink and cities to fund and build such wireless projects. Secure tunneling is the secret sauce for making it work and not making wireless AP owners liable for miscreants who might use the bandwidth, the researchers say."

Comments

Municipal Wireless using existing (private) APs

[compumike]

The first project they discuss is using everyone's existing access points to effectively form a municipal wifi network. The paper linked from the article talks a lot about the security concerns, etc. It's an interesting concept, and I've thought about trying to use the fairly dense wifi network access outdoors in an effort to move data (GPS, etc) between my vehicle and my home.

However, based on my experience with wifi, there seem to be one major problem here: interference effects. I already have problems that I can see about 6 different access points from my desk... on four different networks and SSIDs. The 802.11 spec only allows for three non-overlapping channels (in the US frequency bands, anyway). This problem gets worse as the capacity utilization factor approaches 100%, as it's more and more likely that two packets will happen to collide. This might be a huge problem for this kind of large-scale wifi, as 802.11b/g isn't really designed to operate well when you can see so many APs at once.

In any case, I wonder if they're also overestimating the infrastructure deployment costs. One of the most amazing things to me was how, within a decade, everyone suddenly had wireless in their home and workplace. In fact, in urban areas, it wouldn't surprise me if there were 1 private access point for every 10 or 20 people. People aren't afraid to pay to get cool technology -- although it's a bit different when the government does it.

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Re:Municipal Wireless using existing (private) APs

[RGRistroph]

I don't think that carrying out a full-coverage municipal wi-fi project requires adding access points where there are already access points. That was kind of the point of the article. New access points would be added were there are currently none, possibly. Existing access points would be used where they are available, and traffic tunneled over them in an encrypted form, for social and legal reasons.

I think that this structure should help, not hurt, the access point clashing that goes on in highly dense urban areas. In certain office buildings in particular, there are just too many separate businesses that each want to run their own encryption-protected access point within the physical radius. With this scheme, some of those access points might go away, replaced by using the one local muni-wifi point, with the business willing to do it because they are confident in it's encryption.

Another solution, would be to open up more bandwidth to the 802.11x protocols. That seems unlikely to happen from a political point of view. Maybe if some sort of software radio module became widely available, people could just take some unused spectrum. Encryption and tunneling to share what is already there seems more likely.

Re:Municipal Wireless using existing (private) APs

[mpeg4codec]

It's an interesting concept, and I've thought about trying to use the fairly dense wifi network access outdoors in an effort to move data (GPS, etc) between my vehicle and my home.

You may be interested in this gentleman's setup. It's somewhat light on details, but it proves that it definitely can be done.