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Wireless Everything at Dartmouth

Posted by timothy on from the breaking-ties dept.

hende_jman writes "Dartmouth College in Hanover, New Hampshire is condensing its phone, cable TV, and Internet services all into Wi-Fi, as reported by the New York Times (free registration required). The project, which started in 2001, has added 1400 WAPs and 24,000 wired ports. All that, and cost effective too."

16 of 187 comments (clear)

  1. Everything? by garcia · · Score: 4, Funny

    Those poor Dartmouth students... The future is here!

    Lenina Huxley: I was wondering if you would like to have sex?
    John Spartan: With you? Here? Now?
    [Lenina nods]
    John Spartan: Oh, yeah.

    [after futuristic, contact-free "sex"]
    John Spartan: I was thinkin' we could do it the old-fashioned way.
    Lenina Huxley: You mean... *fluid transfer*?

    Even though contact-free "sex" sounds lame I'm sure wireless beer would be something to rave about!

    1. Re:Everything? by xCepheus · · Score: 5, Funny

      Even though it'd be contact free most /.'rs still probably wouldn't be able to get it.

      *ducks*

    2. Re:Everything? by caryw · · Score: 5, Interesting

      Are they forgetting that these 11Mbps or 54Mbps speeds are the aggregate total for an access point? I hope not.
      Also, if you get a powerful enough microwave or something else that transmits in that 2.4Ghz wavelength it should be fairly easy to bring down the entire campus "phone, cable TV, and Internet services."
      Sounds like fun.
      --
      Fairfax Underground: Local discussion forums for residents of Fairfax County, VA

    3. Re:Everything? by CyberDave · · Score: 4, Insightful

      Not to mention that that aggregate bandwidth of 11 Mbps or 54 Mbps is the bandwidth provided at the raw physical layer. Even when you get to layer 2, you lose a lot of that bandwidth due to all ACKs at the MAC layer, the various timers (inter-frame delays). Then add on top of that the retransmission of lots frames due to interference and you're down to less than 10 Mbps of bandwidth. I've seen data from Vivato that indicates that you get even less than that (around 5 Mbps) in real-world conditions on a 802.11g network. That's about 10% usable bandwidth. Shared. That's not nearly enough. That's enough for maybe one TV channel and nothing else. And don't get me started on the latency...

    4. Re:Everything? by CyberDave · · Score: 5, Informative

      Yes, if the multicasting is done correctly.

      The short answer is that you don't actually have to multicast all twelve billion (slight exageration) channels simultaneously all the way to the set top boxes, just whatever 12 channels the people on the LAN are using (looking at this from the POV of a residential cable system based on Gig-E fiber to the home). If this is done inteligently, you can multicast only those channels being viewed and use IGMP snooping to figure out what to start multicasting from the cable head end. Depending on the exact network configuration (PON, active, etc), the multicast pruning might be done in the network, in the CPE, etc.

      As for bandwidth, yes, it does matter what codec you use, but MPEG-2 for standard resolution TV is 4-6 MB/sec (IIRC). HDTV is another matter entirely, as it's huge (especially when uncompressed).

      I'd write more, but it's time for lunch.

    5. Re:Everything? by NoMoreNicksLeft · · Score: 4, Informative

      The copper is actually short, less than a mile, less than 1000ft in many cases. They use HFC, hybrid fiber/coax. It's fiber nearly until it gets to you. What's more, it's heavily insulated/shielded coax, and has alot more bandwidth than the standard telco loop.

      Contrast this with a telco loop which can be 5+ miles of unshielded copper.

  2. Wireless TV? by Anonymous Coward · · Score: 5, Funny

    What will those crazy kids think of next? Wireless radio?

  3. Brilliant! by Thud457 · · Score: 4, Funny
    Wireless television ?!!!

    Brilliant! Brillant!

    --

    the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff

  4. this seems dumb by eobanb · · Score: 5, Insightful

    Wireless purely for the sake of wireless is just a stupid idea. I'm assuming they pretty much already have most of the infrastructure they need. Don't the dorms and offices and classrooms already have phone lines??? Also, the bandwidth of Wi-Fi is puny compared to gigE, which is what is required for some on-campus applications like streaming video (I'm a student at IU and we do things like that sometimes). Plus there's the whole security problem. This just seems like one big joke...

    --

    Take off every sig. For great justice.

    1. Re:this seems dumb by gunnk · · Score: 4, Interesting

      It depends on what the network was like BEFORE the switch to wireless. If the buildings were all wired with Cat-3 cable to the wall port, why rewire with Cat-5 and then do it again in a very few years when you need fiber or some new Cat-X cable?

      Maybe wireless isn't as good as wired yet, but it isn't that bad either. The overall savings they may realize by no longer having to run new cables to every friggin wall port should more than make up for any cost now. When wifi improves, just swap out the access points.

      --
      Life is short: void the warranty.
  5. No, it's wireless CABLE TV by winkydink · · Score: 4, Insightful

    Now there's an oxymoron if I've ever seen one.

    --

    "I'd rather be a lightning rod than a seismometer." -Ken Kesey

  6. I'm not surprised with Dartmouth by pbooktebo · · Score: 4, Informative

    My brother went to Dartmouth in 1993, and they required everyone to have a computer as they already had campus-wide "blitz mail," which was used a bit like IM. All their assignments were handed in via email, class cancellations were broadcast that way, etc. Everyone was on it.

    Meanwhile, I was at Florida State in Tallahassee, where it wasn't until probably 1995 that you could even easily get a university email (we used to have to set up free city accounts at the public library, which we could then access from campus).

    I don't know that it made much of a difference in his education, but he loved the wow factor and I'm sure that's at play here, too.

  7. Let me get this straight by mattmentecky · · Score: 4, Insightful

    TFA:

    Hardware: Wireless Everything at Dartmouth Wireless Networking
    Posted by timothy on Wednesday May 04, @01:00PM
    from the breaking-ties dept.
    hende_jman writes "Dartmouth College in Hanover, New Hampshire is condensing its phone, cable TV, and Internet services all into Wi-Fi, as reported by the New York Times (free registration required). The project, which started in 2001, has added 1400 WAPs and 24,000 wired ports. All that, and cost effective too."

    Guess it depends what your definition of "wireless" and "everything" is.

  8. AirPwn by crimethinker · · Score: 5, Funny
    I predict increasing use of AirPwn on-campus. See also SourceForge project page.

    Nothing works quite as well as a good, old-fashioned bundle of wires.

    P.S. no connection to the AirPwn folks myself; I just think their particular demonstration project was eff-ing hilarious.

    -paul

    --
    Pistol caliber is like religion: everyone has their favourite, and theirs is the only right choice.
  9. I go to Dartmouth... by theoddball · · Score: 5, Informative

    ...and I work at the helpdesk, no less. I've beta-tested the VOIP rollout and supported the rest. My personal opinion is that the wireless network will NOT hold up well under heavy load once all these services go into widespread use. As it stands now, things slow to a crawl during finals, etc, when people swarm the library and the APs. This is, after all, an 802.11b campuswide network. The backbone is there, but I don't know how the APs will deal with all these latency-sensitive streams. Side note: they've been promoting the VOIP option in the media for months now, but students aren't allowed to get extensions. A little disingenuous, no? Hell, I'd just be happy if the "100% coverage" actually ever gave me a signal in my room. There's some content, and prospects, for this--but so far, it's just PR-fluff.

  10. Re:TV over ethernet by CharlieHedlin · · Score: 4, Informative

    Digital cable and statelite typically use 2-2.5mbits for SD programing. With proper multicasting, QOS, large frames, you could probably get 500mbits onto GigE without trashing the network, giving us 250 SD channels.

    HD mpeg2 needs about 18mbits, and HD divx needs 10-12mbps. I believe DVDs run at 4-5 mbits, and the quality is better than digital cable or satelite.