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Wireless Networking Science Hardware

Cambridge's Streetlamp-Powered Wireless Network 75

Serpentegena writes "A joint research project by scientists at Harvard University and BBn Technologies may have spawned a new breed of Metronet. The wireless network, code-named CitySense, which will consist of 100 streetlamp-mounted nodes by 2011, will draw power off the Cambridge, Mass. public grid and be used at first for weather and pollution monitoring. The intention is to also allow 'academic researchers worldwide [...] to submit their own research programs to run on the network.' Sounds remarkably similar to the beginning of the ARPANET, except the network hosts will be running Linux."
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Cambridge's Streetlamp-Powered Wireless Network

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  • Whoa! (Score:5, Funny)

    by alienmole ( 15522 ) on Friday May 11, 2007 @09:37PM (#19092633)
    100 nodes by 2011? That's like, 25 whole nodes every year between now and then! How are they going to manage such a massive feat of engineering?
    • Re: (Score:2, Funny)

      by nxtr ( 813179 )
      >>How are they going to manage such a massive feat of engineering?
      Let's just say some engineers will have light bulbs going off in their heads.
    • Maybe that's the rate that the light bulbs burn out at, and they're installing these things at the same time to save labor?

      (I'm sure if we knew the number of total streetlamps in Cambridge, and the average lifespan of a Na- or Hg-vapor lamp, someone around here could probably compute the average number per year that would need replacement.)
    • Re: (Score:3, Funny)

      by Plutonite ( 999141 )
      Was gonna crack the ole Beowulf cluster joke, then realized it would take them till the year 2460 or something to build it. I honestly don't understand how such small number can be of analytical utility. It would be great if someone could volunteer to RTFA and inform us.
      • Re: (Score:2, Funny)

        by coleblak ( 863392 )
        Whoa, whoa, whoa. You want us to read an article? I thought slashdot was all about spouting off opinions without reading anything?
  • Programs? (Score:2, Interesting)

    by QBasicer ( 781745 )
    Why would there needed to be programs run on the network, if all the nodes are is data collecting points? Wouldn't it be easier to just store the data and replicate it for later analysis?
  • by Anonymous Coward on Friday May 11, 2007 @09:46PM (#19092687)
    I hear these network nodes will have flashing LEDs which will drive the local police forces apeshit.

    Expect many lawsuits and unjust imprisonment.
  • by Anonymous Coward
    I just mount solar panels underneath the street lamps and then use the generated power to run the lamps! Ingenious!
  • It's been done. (Score:3, Interesting)

    by HaeMaker ( 221642 ) on Friday May 11, 2007 @09:51PM (#19092721) Homepage
    Anyone from SF bay area, Denver or Washington DC remember Ricochet? []
    • by the_tsi ( 19767 )
      That was exactly what I thought of when I saw the word "streetlight". And after that I thought, "Man, what more cities need is a shitty proprietary wireless serial link to a low-speed wifi mesh! Then they can charge too much for it and get about four customers!" Those Ricochet guys had a PLAN!
      • Re:It's been done. (Score:5, Informative)

        by Loconut1389 ( 455297 ) on Friday May 11, 2007 @10:29PM (#19092947)
        56K modem speed (for their second generation network) was quite impressive in its day- considering most people were still connecting to the internet at 19.2 at the time. The first generation network was still impressive. Sure 14.4 and 56K sound slow nowadays, for the buck it really was amazing. I remember the first time I sat down at a barnes and noble with my laptop and got on IRC and I was just flat out blown away. I knew lots of people who had it and it seemed they were poised to do quite well. For some reason the died off before WiFi really was accessible, and I never understood quite why. They seemed to have little problem negotiating WAP placement deals. Anyway- that proprietary wireless network predated 802.11 (I think) and was the only way to go for wireless. Its not like they jumped on when wifi was already around and said 'hey try our slow network instead'.
        • by SuperQ ( 431 ) *
          AFAIK 802.11 (no letters, FHSS not DSSS RF mode) was around at the time.. but was usually in the form of over priced flakey breezecom gear. They were still 2mbit, and had way better latency than ricochet.

          What really killed ricochet was it's expensive licensed commercial spectrum, which translated into high customer access costs.
        • Re: (Score:2, Interesting)

          by sunspot55 ( 305580 )
          I used to work at Metricom and I can say that your 56k speed was VERY conservative. I believe they advertised 128k and we would routinely get 192k in the lab. It was faster than ISDN, which was your main option for high speed internet at home at the time (DSL was just starting to be released). Oftentimes the serial speed was limited by the RS232 data speed (I think the RS232 port speeds defaulted to 56k often). Both USB and RS232 were options on the Gen 2 modem and I recommended using the USB to anyone
          • I had a gen 2 modem at the very beginning of their existence (2nd/3rd SF Robot Wars (before it became Battlebots) era). They were only advertising 56k at that time. Unfortunately, after a day of running around with my laptop under one arm, climbing bleachers, and being wreckless with my laptop at Robot Wars, I stopped at a friends house on the way and when getting ready to go home I picked up the laptop in a hurry only to not quite get ahold of it and watch it land upside down on soft carpet from 1 foot or
          • by markana ( 152984 )
            With my Gen-1 Ricochet as my home net connection, I regularly got 112K thoughput. It was *way* better than any dial-up at the time. I liked it so much that I bought a 2nd modem for my laptop, and had pretty good mobile connectivity anywhere in the area. Metro WiFi is only now getting to be as good as Ricochet was years ago....
    • Didn't know metricom was back in business- weird now that they have no chance with wifi hotspots catching on and being so easy to implement (and EV-DO for that matter). They're using 'a micro cellular data network' now supposedly. I had one of these back in the day- had to velcro a modem to the back of my LCD on my laptop and it had a cool looking RGB led (had never seen one of those before) and it could do a peer-to-peer network in the absence of a metricom network- that was pretty fsckin awesome at the ti
      • Re:It's been done. (Score:5, Informative)

        by Myself ( 57572 ) on Friday May 11, 2007 @10:55PM (#19093067) Journal
        EVDO can't support the subscriber density that Ricochet can/could. Get a dozen active users per square mile and EVDO gets pretty sluggish. Ditto with EDGE/HSDPA.

        Wireless data is driven by the principle of geographic frequency reuse. If you can make short-distance transmissions, you can use less power, which means there can be someone else using the same channel just a short distance away. If you're far from your tower and need a lot of power, you tie up the channel for a wider area, meaning that fewer subscribers can be satisfied per unit of spectrum.

        With a microcellular network like Ricochet, there are several poletops per square mile, and the same channel might be in use several times within a square mile. With cellular towers, a single sector usually serves several square miles, so a lower user density saturates the spectrum. Ricochet never achieved user density to come anywhere close to capacity, whereas many urban EVDO sites run maxed out for hours a day.

        Metricom's Ricochet was ahead of its time, and not marketed effectively. They built a very dense, capable network, anticipating the internet growth that didn't materialize until many years later. They didn't have the financial resources of a giant cellular company to weather the lull, and their recurring costs killed them. Their assets were sold at auction, and have since changed hands several times. YDI/Proxim currently maintains Ricochet networks in the cities where they inherited contractual obligations, but the rest of the markets sit abandoned.

        Ricochet's still relevant in areas where cable and DSL aren't available, because while not speedy by today's standards, it wipes the floor with dialup and is more than adequate for most uses. The deployment cost is dirt-cheap, and the modems can be had for a song. That's part of the problem though, because you can't sell a customer a $100 modem if they can get it for $5 on eBay.

        The modems are also useful for peer-to-peer networking over distances that wifi can't touch. They do a mile in open space, and half a mile pretty reliably in an urban environment. The 900MHz band is wide open, and penetrates buildings much better than 2.4GHz. If you get 'em above the terrain, they'll do five or ten miles on the stock antennae. There's some user-driven research on the Ricochet Wiki [] if you're interested.
        • by garcia ( 6573 )
          Ricochet never achieved user density to come anywhere close to capacity, whereas many urban EVDO sites run maxed out for hours a day.

          What you say is true but I was shocked with my speeds on T-mobile's EDGE network in Los Angeles compared to Minneapolis'. LA's speeds were quite a bit faster than what I experienced at home while I was expecting it to crawl along sluggishly.

          The phenomenon you mention is most noticeable when I move from the metro into areas like rural IA and roam on I-Wireless. Their speeds a
    • by Lumpy ( 12016 )
      Anyone remember packet radio? Packet Radio predates richochet by at least 10 years.

      • Anyone remember packet radio? Packet Radio predates richochet by at least 10 years.

        Packet radio, however, is hardly dead -- yeah, it's not exactly impressive to tell people "hey, I'm on the internet...over a radio" anymore, but there are still a lot of people doing some very impressive mobile stuff with APRS on VHF, or long-distance connectivity over HF.

        Not long ago I went to a lecture by a ham who had spent some time down in Central America building an email system based on packet radio for some humanitari
        • by Lumpy ( 12016 )
          I actually have. I just recently took down 8 digipeaters I had on the air on 2 meters and sold all the gear on ebay.

          The digi's have not been used for over 24 months by anyone but me, I gave up supporting a large packet network that nobody was willing to help with and the users dropped to zero because packet use has dropped to zero as 1200baud is too slow for anything anymore. APRS use around here has dwindled to nothing as well.

          2 meter repeaters has turned into CB radio around here.
    • Metricom was the first stock I ever owned. I still feel a sense of geek pride when I see them.

      I wish this technology had kept moving... lots of opportunity for mesh networks to help with local and mobile network access.
    • A few entities tried to purchase the Ricochet infrastructure in the San Francisco Bay Area, simply for their positions on the poles and contracts for use, but all stopped when they realized PG&E (Pacific Gas & Electric) was holdig a $60 million warrant on the assets for the power they had been drawing since the service was terminated. Seems that the radios have been on the whole time. Two suggestions:
      1. Build remote shutdown into the radios.
      2. Make them field upgradeable, so they're unlikely to be 1
  • Would be sweet. I think we need more pollution here to get something like that too!
  • They've been around at LEAST since Ricochet (1994).
    • Cities all over the USA have been mounting 2.4GHz wireless mesh nodes onto streetlamp poles for several years now. It's bloody expensive to cover an entire city with these, you need about 20 nodes per square mile for decent coverage and the technology doesn't scale very well and tends to implode under stress and large number of nodes.
  • by jddj ( 1085169 )
    They're using a unique new design for the access points []
  • Been done before... (Score:2, Interesting)

    by ZeldorBlat ( 107799 )

    How is this any different than any other municipal wireless project? I suppose it's different because it isn't intended to actually provide public wireless internet access (in the short-term, anyway).

    Oakland County, MI is currently implementing a wireless network [] across over 900 sq. miles. Granted the free service is pretty slow (128 kbps), but the for-fee service being offered [] is competitive with cable offerings in the area.

  • by daeg ( 828071 ) on Friday May 11, 2007 @10:40PM (#19092999)
    I read the headline as "Cambridge's Steam-Powered Wireless Network". It was far more interesting with a wrong title. Maybe they should change the focus of their research.
  • Metronet? (Score:5, Funny)

    by Dachannien ( 617929 ) on Friday May 11, 2007 @10:56PM (#19093075)
    Metronet, huh? Is that like an Internet for really well-groomed straight guys? []

    • No, it's Internet for a well groomed MAN ;)
    • Metronet, huh? Is that like an Internet for really well-groomed straight guys? []

      ...I'm guessing that's no more the case than a metrocard on the Metro Transit Authority railroad and the Met[ropolitan Opera] and only for well-groomed, straight guys. Actually scratch the last one.
    • by ch-chuck ( 9622 )
      Even more offtopic, isn't it funny how people rediscover old ideas [] and think it's something new.
    • the D/FW Texas "Metroplex". I don't think they're in business anymore, but they used to be one of the pioneer ISPs there. One of my former employers back in the ancient days had one of the very first 56K frame relay commercial Internet feeds sold by Texas Metronet.
    • You do know that the metro- prefix has been in use since Ancient Greece, right? At the time it meant 'mother' (the name of the Mother Goddess), as in the mother city (metro-polis) of a colony, but for well more than a century has been used as an English prefix, meaning 'of the city'.

      Ancient roots used to be covered in 5th grade English - sorry if I'm being age-ist and am unfairly criticizing somebody who hasn't yet covered that in school.
      • sorry if I'm being age-ist and am unfairly criticizing somebody who hasn't yet covered that in school.

        Teach me more, Grandpa!

  • by Tetravus ( 79831 ) on Friday May 11, 2007 @11:11PM (#19093139) Homepage

    The author of the article doesn't emphasize that the interesting thing about this network (besides it being associated with Haaaavard and therefore news-worthy to certain people) is that it's a distributed sensor network. It doesn't just pass data between nodes, each node is capable of creating and sharing data with the rest of the network. In fact, that's the only thing that's interesting about this at all. I mean, did Google force Mountain View to install new wireless node poles when they put in their WiFi or did they just piggyback on existing infrastructure? And, as someone else has mentioned, Ricochet networks did the whole city-wide data network thing in the late 90's.

    So, if you've been looking for a place to test out your predictive models of chemical dispersion under real-world conditions, it sounds like Cambridge is the place to go.

    • Actually, Ricochet poletops can be used to infer certain environmental conditions too, specifically the propagation of 900MHz and 2.4GHz signals. You can do this indirectly, by watching packet headers and tracking the paths that packets take between radios (longer hops if conditions are good), which has been done in at least one area for some time now. It's fascinating data; I hope to have pretty animated graphs of it some time soon. You could also do it directly, by interrogating each radio's node table pe
  • Similar Thing Here (Score:3, Informative)

    by Comatose51 ( 687974 ) on Friday May 11, 2007 @11:14PM (#19093165) Homepage
    Google Wifi is deployed here in Mountain View and they're also posted on street lamps. Is it just me or does this plan just not sound very impressive. Google's system is quite interesting. Every now and then there's a very massive and obvious wifi AP up high on a pole. The rest of them would be hidden inside the street lamps and all they do is relay traffic back to the other ones. This saves them from having to actually wire every lamp post.
  • Interesting that you mention how this is like the beginning of the ARPANET considering that BBN created the ARPANET back in the late sixties! (and out of respect it's BBN, not BBn)
  • by Rethcir ( 680121 )
    Hey make sure don't forget to mention linux
    • Yeah, but does it run...


      In Soviet Russia, Linux runs...


      All your unix-base are belong to...


  • Cambridge and MIT are already building a FREE public access Wi-Fi system called roofnet.

    They started long []

    Interestingly harvard has stated plans to join roofnet. /2006/02/02/cambridge_mit_plan_citywide_wifi/ []

    The notion that a few weather sensors spead out over a tiny tiny tiny land area the size of cambridge MA somheow represents something significant is pathetic. That someone actually expended the effort and column s
  • I happen to be one of the lead investigators on the CitySense project. It's cool to be slashdotted; and funny to read the comments from people who jump to incorrect conclusions based only on reading this fairly high-level and (admittedly not very good) article. If you want to know more check out our web page: []. One of the big problems with popular press is that it is not targeted at folks who read Slashdot and crave the technical details.

    CitySense is intended to be the first (to our
    • A whole city grid of sensors and what could you do with it? Well, with IPv6 and ubiquitous RFID you could provide the means for everyone in a given area to be tracked and their movements monitored down to the square meter. Thieves would never be able to steal anything since the items they have would be tracked to wherever they go to and cross tracking of their IDs would give you everything that you needed to apprehend the scofflaws. Of course, everyone who chose not to take the chip would be an 'illegal' a

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