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San Francisco's Got Free Wi-Fi

Posted by timothy on from the leave-your-heart-and-brain dept.

Carpoolio writes "If you're living in San Francisco, chances are you can connect, for free, to the BARWN -- the Bay Area Research Wireless Network. BARWN broadcasts an 802.11 signal from the top of a big hill near San Francisco, and anyone with a clear sight line to the signal can connect. Another set of wireless nodes are being placed around town by SFLan, making Wi-Fi available to tens of thousands of people."

45 of 156 comments (clear)

  1. hmmm by Anonymous Coward · · Score: 4, Funny

    Free as in WIFI?

  2. Overloaded? by AKnightCowboy · · Score: 4, Interesting

    Wow, that must be some magic access point. Mine can only handle about 30 people before it's saturated. How did they overcome that limitation of 802.11b?

    1. Re:Overloaded? by asquared256 · · Score: 5, Insightful

      There are most likely multiple access points operating on different channels, and in different areas. It's probably not a single AP.

    2. Re:Overloaded? by DietFluffy · · Score: 3, Informative

      More specifically, each custom router can employ up to 9 APs.

      Barwn Outdoor Wireless Router Whitepaper

  3. RIAA Sues City of San Francisco ! by Anonymous Coward · · Score: 3, Troll

    ... it will happen

  4. Not quite everyone by paul248 · · Score: 5, Informative

    According to the article, The hill has a few directional antennas that provide access to 30 or so stationary access points scattered around the area. I assume those access points also have directional antennas pointing back. This would seem to indicate that in order to get online, you have to be near one of the access points, not simply in view of the hill.

    1. Re:Not quite everyone by anthony_dipierro · · Score: 5, Informative

      This would seem to indicate that in order to get online, you have to be near one of the access points, not simply in view of the hill.

      Ah, but it also says:

      If you live within eight miles of San Bruno Mountain and have a place -- a rooftop often does well -- that provides a direct line of sight to the mountaintop, you can buy and build your own access point.
  5. spammers paradise by adept256 · · Score: 5, Insightful

    Can anyone tell me the likelihood of tracking down a spammer at a laptop in a city the size of San Francisco?

    --

    I ran a benchmark on my quantum computer, now I can't find it anywhere!
    1. Re:spammers paradise by t0qer · · Score: 4, Informative

      Can anyone tell me the likelihood of tracking down a spammer at a laptop in a city the size of San Francisco?

      SF is not as big as some people think it is. Compared to neighboring cities you could probably fit 3 SF's in Oakland, and as many as 5 in San Jose.

      As far as tracking spammers, when I worked at ricochet we recovered a laptop stolen from a trade show in San Francisco once. Wasn't really that hard once we had the modem # and triangulated it's position from the poletops it saw. From there it was just a matter of pinpointing its location with a loop antenna.

    2. Re:spammers paradise by Rosco+P.+Coltrane · · Score: 5, Funny

      SF is not as big as some people think it is. Compared to neighboring cities you could probably fit 3 SF's in Oakland, and as many as 5 in San Jose.

      I'm sorry, that doesn't speak to me much : just so I have an idea, how many SFs would you say fit in one Library of Congress?

      --
      "A door is what a dog is perpetually on the wrong side of" - Ogden Nash
    3. Re:spammers paradise by mog007 · · Score: 3, Funny

      I don't know about that, but I do know that one SF weighs approximately one hundred thousand elephants.

      --
      Learn something new.
    4. Re:spammers paradise by Texas+Rose+on+Lava+L · · Score: 2, Informative
      I'm sorry, that doesn't speak to me much : just so I have an idea, how many SFs would you say fit in one Library of Congress?

      Library of Congress: 2,100,000 square feet
      San Francisco: 46.7 square miles

      Google says that "2100000 square feet/46.7 square miles" is 0.001613.

      :-)

      --

      Rank Presidents by th

  6. Regardless by bluedust · · Score: 3, Funny

    It really doesn't matter if it's 802.11b, a, or g.. within minutes the connection will be slashdotted and brought to its knees.

  7. WiFi VOIP by tobes · · Score: 4, Interesting

    It'll be nice when things like this become ubiquitous and someone starts manufacturing WiFi "cell" phones that use Vonnage or some such thing.

    It's been my experience that iChat has near cell sound quality, so having a small hardware iChat (or whatever you use) client with 802.11b access would be pretty sweet.

  8. Speed problems? by justbsd · · Score: 5, Funny

    Just blanket the city with this and we're set.

  9. Silly you by Anonymous Coward · · Score: 2, Insightful

    You're operating under the premise that I pay taxes! I don't!

  10. SBC Surrenders. by tinrobot · · Score: 3, Interesting

    So, does this mean people in SF can cancel their broadband connections and go 100% WiFi?

  11. Not for much longer... by advocate_one · · Score: 4, Insightful

    It will be brought to it's knees from the sheer mass of freeloading P2P traffic, not to mention all the worms looking for fresh hosts to infect.

    --
    Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
    1. Re:Not for much longer... by Saeger · · Score: 2, Interesting
      There's no reason routers (wireless or not) have to be so stupid.

      Throttle the connections based on a moving average of bandwidth usage, then your average Joe can get his email @ max speed, and your average Jane can download her 100MB of wedding pictures @ medium speed, but Johnny 24/7 Pirate will stuck at the remaining capacity (slow) speed.

      --

      --
      Power to the Peaceful
  12. Does anyone benchmark these? by vudufixit · · Score: 5, Interesting

    Look, no one should complain about a "free" connection, but I'm curious to know how fast the typical user's connection really is. After all, the access point has to be connected to a terrestrial data line, which has limited bandwidth. Of course, the more people find out about this, the slower it gets for everybody, right? Does anyone know if those who provide "free" wireless access have an upgrade plan to handle the additional traffic?

  13. P2P on public WIFI by Eberlin · · Score: 5, Insightful

    Most folks think spam when it comes to large wireless networks. I'm thinking P2P -- it'll be a bit tougher to trace shared music across a public wireless network than it would be on someone's home DSL connection.

    Of course this could also be a haven for computers that don't have the latest patches, have print/file sharing enabled, and don't have personal firewalls activated. For those who want to run in this, be careful.

    1. Re:P2P on public WIFI by timeOday · · Score: 2, Interesting
      Of course this could also be a haven for computers that don't have the latest patches, have print/file sharing enabled, and don't have personal firewalls activated.
      No more so than the wired Internet. (And what is a "personal" firewall?)
  14. Ganging APs for more WiFi bandwidth by G4from128k · · Score: 3, Interesting

    It would seem that if you have a clear line of sight to multiple APs, then you could combine them and have more bandwidth than a single AP-channel connection would provide. A ganged, multi-AP setup would use directional antennas to talk to each AP without collisions. Such a setup would also help if one AP were overloaded or down for some reason. The only problem would be if all the APs you talk to were routed through some narrow pipe somewhere in the network.

    --
    Two wrongs don't make a right, but three lefts do.
    1. Re:Ganging APs for more WiFi bandwidth by PureFiction · · Score: 4, Informative

      It would seem that if you have a clear line of sight to multiple APs, then you could combine them and have more bandwidth than a single AP-channel connection would provide.

      This is called "concurrent multiple association" or simple multiple assocation / AP hopping, and it's something i've been working on off and on for a little while. I talk about it in a bit more detail on the Janus Wireless pages, but I have yet to get anything stable ready for prime time use.

      The current problem with multiple association is that you need a very low latency interface to the network radio's at a packet injection / monitor mode level.

      I've been able to get this to work in a very crude and inefficient manner with cisco/prism cards used for monitor mode recv of packets, and prism2 based cards for packet injection to implement the multiple association and data packet injection.

      There is some hope that the newer cards, specifically the atheros 802.11a/g cards with a reversed binary HAL driver could provide the requisite low level functions to do this efficiently.

      But then you are faced with another problem: aggregating the UDP datagrams from multiple sources into a single address space similiar to the way mobile-IP has a dedicated "public" host which acts as your intermediary as your IP changes without breaking existing TCP connections.

      I've played with this a bit as well on a dedicated host that has a few IP's, and it works like a NAT that collates UDP datagrams from a wide variety of sources and converts them into the desired TCP/UDP/etc communication from that public endpoint.

      In short: for multiple association you need a number of new driver and radio interfaces for:

      1) very low latency packet injection and monitor style recv.

      2) specialized mobile-IP like drivers on the client that present a virtual interface (ethX) to then host while using injected datagrams over the various multiply-associated wifi links for transport.

      3) a dedicated public host with an IP it can allocate to you that accepts all of these incoming UDP packets from various source addresses (all the AP's you are using) and combines them into standard IP traffic from that public IP (ala mobile-IP as well).

      None of this is extremely difficult (with the newer cards) but it is a lot of code, and a lot of work, and requires some dedicated host resources.

      Now, for the cool part. When you do have all of these pieces in place, it allows you to:

      - Simply add cards to your system for more bandwidth. The multiple association throughput is limited only by the number of AP's you can talk to, and the number of cards you have to monitor and inject packets with. It scales nicely barring interference problems.

      - Maintain extremely high throughput as you move anywhere within range to open AP's! You could aggregate the upload capacity of 30 AP's to get a 10Mbps link to the net and maintain this constant fat uplink as you drive around the city.

      - Enjoy extremely reliable / robust communications. Since you are no longer dependant on a single AP, you dont have to worry about connection dropping, clients messing with your signal, etc. Your aggregate connection is spread over a number of AP's which means problems with individual AP's make only a very small impact on overall connectivity.

      This is really the way things are headed, and its only a matter of time before they become useable and widespread.

  15. Monetize THIS! by Saeger · · Score: 4, Interesting
    "Tim says he set up the network because he wants to give Internet access to people who can't afford or access it, especially people living in Third World countries or depressed areas of other countries."

    The thing about free wireless (that I love) is that it keeps the Ashcroft-types up at night worrying about anonymous "terrorist" freespeech, and it gives the telco-types and the WISP-wannabes the middleman middle finger.

    Community owned and operated, adhoc wireless mesh networking will be the future of free ubiquitous access despite some peoples early attempts to coopt it. It's similar to how FedEx thought they could own the Fax business in the 80s. Can't blame 'em for trying I guess.

    --

    --
    Power to the Peaceful
    1. Re:Monetize THIS! by anthony_dipierro · · Score: 2, Interesting

      Community owned and operated, adhoc wireless mesh networking will be the future of free ubiquitous access despite some peoples early attempts to coopt it.

      Nope, mesh networking (as described in your link, anyway) will never be free. Someone has to pay for those "stems reaching into the Internet," after all. The current system of semi-centralization is much more efficient than a mesh network. You run a bunch of connections to a central location, then you run a single big connection between those locations. The telephone network wasn't built this way by accident. It was built this way because it is the most efficient way to do things. Sure, wireless is cheaper than wires, but it still costs money to both set up the point to point links (I know you're not talking about broadcast links), and to send the actual data (think electricity costs).

    2. Re:Monetize THIS! by Saeger · · Score: 2, Insightful
      Obviously the intercity/interstate/etc hierarchy of fast fiber links won't be replaced by slower wireless nodes, but mesh networks plus those fewer stems would be much cheaper and more useful than having some megacorp own the local wired/wireless every step of the way.

      --

      --
      Power to the Peaceful
  16. Hmm, super by Rosco+P.+Coltrane · · Score: 4, Funny

    from the top of a big hill near San Francisco, and anyone with a clear sight line to the signal can connect. Another set of wireless nodes are being placed around town by SFLan, making Wi-Fi available to tens of thousands of people

    In other news, the CDC and the Cancer Research Institute have sent observers in the city of San Francisco. When asked about their presence, CDC operatives declared they were here to monitor the results of an undisclosed "full-scale experiment".

    --
    "A door is what a dog is perpetually on the wrong side of" - Ogden Nash
  17. Re:Repeat after me. by anthony_dipierro · · Score: 5, Informative

    This is paid for by tax dollars

    Actually, it's paid for by the Bay Area Wireless Users Group

    That doesn't make it free, it means you already pay for it with the taxes you already pay.

    Also, it's not clear if they meant free as in beer, or free as in freedom. If they allow anyone to go online without registering or anything, then it's both!

  18. Another city has had it for a year or so... by NineNine · · Score: 2, Informative

    Carrboro, NC

  19. hmm by prockcore · · Score: 3, Funny

    I left my AP in San Francisco
    High on a hill, it calls to me
    To be where signals are 3 bars,
    my ISP is 4 stars.
    My network is in the air, I don't care

  20. Not really new news... by faedle · · Score: 3, Interesting

    But, hats off to yet another group of intrepred geeks. San Francisco has been a hotbed of free WiFi service for quite some time, be it organized efforts like the aformentioned SFlan or ad-hockery created by people setting up intentionally open WiFi nodes in their homes and businesses.

    When I lived in SF, I got in a heated debate with a guy named Scott regarding whether all of this 802.11 ad-hockery was stealing from the phone company. He was largely a troll, never really arguing any points directly and shifting focus: but you can see the results at my website. He's even come back way after the fact and submitted comments in my comment section.

    The reason I bring up this discussion is because I think Scott's misconceptions about what people are doing with 802.11 open access points brings up a serious issue. Read what he has to say: and read between the lines for the greater position that he stands behind. It's a scary thought to consider that people believe that the phone companies have a right to make money, regardless of how badly they mishandle their markets.

  21. New element for the periodic chart by Anonymous Coward · · Score: 2, Funny

    A major research institution has recently announced the discovery of the
    heaviest chemical element yet known to science. The new element has been
    tentatively named "Governmentium". Governmentium has one neutron, 12
    assistant neutrons, 75 deputy neutrons, and 11 assistant deputy neutrons,
    giving it an atomic mass of 312.

    These 312 particles are held together by forces called morons, which are
    surrounded by vast quantities of lepton-like particles called peons. Since
    Governmentium has no electrons, it is inert. However, it can be detected as
    it impedes every reaction with which it comes into contact. A minute amount
    of Governmentium causes one reaction to take over four days to complete when
    it would normally take less than a second.

    Governmentium has a normal half-life of three years; it does not decay, but
    instead undergoes a reorganization in which a portion of the assistant
    neutrons and deputy neutrons exchange places. In fact, Governmentium's mass
    will actually increase over time, since each reorganization will cause more
    morons to become neutrons, forming isodopes. This characteristic of
    moron-promotion leads some scientists to speculate that Governmentium is
    formed whenever morons reach a certain quantity in concentration. This
    hypothetical quantity is referred to as "Critical Morass." You will know it
    when you see it.

    When catalyzed with money, Governmentium becomes Administratium -- an
    element which radiates just as much energy since it has half as many peons
    but twice as many morons.

  22. Obligatory NoCat.net Link by ksw2 · · Score: 2, Informative

    If you're interested in community-sponsored wifi projects, you should take a look at this. It's run by Rob Flickenger, the guy who wrote Linux Server Hacks and a couple of wifi books for O'Reilly.

  23. Wireless Tutorial by ksw2 · · Score: 2, Informative

    If you are new to wireless networking, I stumbled across this tutorial.

  24. Lies by MrCawfee · · Score: 2, Interesting

    This lies, i have line of site to twin peaks and i can't connect, it's all lies! but i can connect to my neighbors open ap called "default"

    1. Re:Lies by Anonymous Coward · · Score: 2, Funny

      maybe you should try aiming your pringles can a little better, amateur

  25. Re:its about time by ziggyboy · · Score: 2, Insightful

    I've lived in 1 third world an 2 first world countries before. Setting up city-wide WiFi on third world countries would be a waste of their money. For one thing, they would only be catering to a niche of the society who could afford WiFi-enabled devices. Secondly, it would be too expensive for any third world country institution to be offering free internet access....much less buy WiFi equipment to handle that kind of load.

  26. Cheesbikini by Omniscient+Ferret · · Score: 2, Informative

    There are also a ton of restaurants & cafes in the area that offer laptop access - cheesbikini offers a good list of them.

    I have a flaky wireless connection at home; I'd order a cantenna with pigtail but I prefer paying cash...

  27. Re:Awesome by MikeCapone · · Score: 2, Insightful

    No more bugging my friends when I'm making plans on the fly in the middle of the city and asking them to Google something for me (address, event time, etc :) I'll just have my laptop in my car...

    Please google "driving safely" first. kthx

    --
    Treehugger? Treehugger... Treehugger!
  28. legalities by null-sRc · · Score: 2, Interesting

    what are the legal implications in the event of malicious activities performed over such a open network.

    ie:

    - child porn downloading / trading ?
    - will the riaa sue for all the mp3's downloaded ?
    - an anonymous way to spam ?
    - etc :D

    unfortunatly a few bad apples always ruin the party for the rest of us. :(

    --
    -judging another only defines yourself
  29. and for those in the NYC area.. by LoganEkz · · Score: 4, Informative

    There are tons of free hotspots in the New York City metro area as well.

  30. taking care of illegals? by matth · · Score: 2, Interesting

    So exactly how are they planning on dealing with hackers and the like? Sounds like a great place to hack from! Get on.. do your stuff.. get off!

  31. A few clarifications by Danton · · Score: 5, Informative
    ...for those few who didn't RTFA (I heard that happens on /.)

    I am one of the people building SFLAN. Our map is a little outdated (and the San Bruno Mountain node is in the wrong spot). SFLAN and BAWRN have some 30 nodes in as many locations in San Francisco and a few outliers in surrounding counties. If you are in San Francisco and want to try it out, Cole Street is well covered. The SSIDs are sflanNN or BARWN-xxxxx; DHCP, no WEP.

    The nodes are owned and paid for by individuals, many of whom are members of the Bay Area Wireless User Group. The Internet bandwidth for SFLAN is sponsored by the Internet Archive. If you live in SF and want to buy a node to connect your house and your neighbors, contact us.

    We like to keep these networks as free (as in speech and beer) as possible. And it's working out so far. I hear Tim Pozar's neighbors keep him happy with occasional pies...

    --
    "Web Users Should Not Engage in Promiscuous Browsing" --CERT
  32. Network Map by rtnz · · Score: 2, Informative


    Here is the Network Map: http://www.barwn.org/docs/BARWN_networkmap_200202. jpg

    L