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Private Networks For Public Safety 45

JonZittrain writes "Projects like the New American Foundation's Commotion are designing ad hoc mesh networking to keep communications open when governments want to censor. Former FCC Chairman Julius Genachowski and I argue that mutual-aid-based networks can be helpful for public safety, too, after attacks or natural disasters. There should be easy practices for anyone to open up an otherwise-closed Wi-Fi access point if it's still connected to broadband and is near people in trouble, and separately, to develop delay- and fault-tolerant fallback ad hoc networks so users' devices can communicate directly with one another and in a mesh. This can happen even while full packet-based ad hoc mesh is being figured out. The ideas have been developed a little in workshops at Harvard's Berkman Center and the FCC. Why not bring the human rights and public safety communities together towards a common goal?"
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Private Networks For Public Safety

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  • by mspohr ( 589790 ) on Friday June 07, 2013 @11:43AM (#43936941)

    Looks like these people are working on something similar:
    http://project-byzantium.org/ [project-byzantium.org]

    • I would donate so cash if someone could could port this to ARM, specifically Raspberry Pi or BeagleBoard Black.
      • by mspohr ( 589790 )

        I think that's already been done:
        http://project-byzantium.org/isc-grant-milestone-number-one-achieved/ [project-byzantium.org]

        • "I think that's already been done..."

          It needs to be an app, not an OS.

          • by mspohr ( 589790 )

            It is an app and runs on x86 and RaspberryPi.
            If you have a WiFi device (smartphone, etc.) you just connect to the app.
            If you'd like your smartphone to run the app, you could help port it.

            • Read the damned article you linked to.

              It is an OS, not an app. But they did get it working on the Raspberry Pi.
              • by mspohr ( 589790 )

                Hi Jane,
                I think you need to do a little remedial reading on the definition of OS and apps.
                In brief and without getting too nit picky technical, the OS interfaces with hardware and provides services to apps.
                Byzantium is a set of applications which run on an OS (Linux).
                Byzantium is not an OS, Linux is an OS.
                You could port the Byzantium set of apps to another OS.

                • "I think you need to do a little remedial reading on the definition of OS and apps."

                  I think YOU need to practice a little remedial reading, PERIOD.

                  BYZANTIUM IS A LINUX DISTRO. It is not just an "app" that runs on Linux.

                  Quote from their own home page: [project-byzantium.org]

                  "Byzantium is a live Linux distribution..." [emphasis added]

                  Further, the original post linked to this page [project-byzantium.org], which says they got their Byzantium Linux (not app) to run on the Raspberry Pi.

                  Holy crap, man, do you even read the stuff you're arguing about?

                  There is a BIG DIFFERENCE between an app and a Linux distribution. Further, a Linux distribution is not "just Linux".

                  "Byzantium is a set of applications which run on an OS (Linux).
                  Byzantium is not an OS, Linux is an OS.
                  You could port the Byzantium set of apps to another OS."

                  So what you're saying i

      • by Anonymous Coward

        Then why don't you donate so that they *can* port this to ARM (specifically Raspberry Pi or BeagleBoard Black).

  • by earlzdotnet ( 2788729 ) on Friday June 07, 2013 @11:44AM (#43936957)
    If we build a mesh network to communicate, then how will the NSA listen in? They'd have to dispatch someone to every disaster to ensure they had a node in the mesh that could listen in. That would cost us taxpayers way too much money
    • by Picass0 ( 147474 )

      If one of the devices on the network has a backdoor, which it's starting to appear most of them do.

      • by mspohr ( 589790 )

        Best to use all open source software.
        Open source is unlikely to have a back door. If one is there, it will be quickly found and patched.

    • Concerned taxpaying patriot citizens should opt in to helping the NSA on a volunteer basis.

      NSA should provide a spec for device driver writers to make alternative null devices, such that machines which opt to use this driver, anything written to the null device would be automatically sent to NSA. Then all software could be changed to divert a copy of all streams to the null device. For people who don't opt in, there's no privacy risk. For concerned taxpaying patriots who wish to share with NSA, they just

  • by godrik ( 1287354 ) on Friday June 07, 2013 @11:49AM (#43937021)

    I was always wondering how you achieve routing and addressing in a completely adhoc network. Let us assume that my whole city put their wireless access point in ad hoc mode even on the same SSID or whatever. How do you achieve any form of coherent addressing and routing ? You do not want to follow the ethernet technique with huge arp tables, devices are never going to be have enough memory to store such huge tables. Routing will be completely inneficient.
    Any idea?

    • Re: (Score:3, Informative)

      by Anonymous Coward

      B.A.T.M.A.N. [wikipedia.org]

      • by godrik ( 1287354 )

        Good try but batman does not scale. You essentially need an arp table (or whatever the terminology in batman is) which is as large as the number of entities in the network [1]. Batman is essentially a broadcast based protocol: It will congest the network extremely fast. It probably wont scale to city scale. Note that I am not sure there is a good scalable existing answer to adhoc mesh routing.

        [1] http://www.open-mesh.org/projects/open-mesh/wiki/FAQ#How-big-networks-does-batman-adv-support [open-mesh.org]

        • Re: (Score:3, Interesting)

          by Anonymous Coward

          You could reduce the ARP table down to two seperate, but much smaller tables: The first table is a list of known hosts and their last known routing neighbor, with aging and maximum size stack dumping. Keep this at about 1024 entries. The next table is a hash of the addressing schema which weights each of your local neighbors for each address range hash. You can keep this down to 65536 hash groups and highest scoring neighbor for discovered source address packets transmitted. You can expand this in one

    • I was always wondering how you achieve routing and addressing in a completely adhoc network. Any idea?

      I wouldn't have a clue, but other people do, luckily: http://www.open-mesh.org/projects/batman-adv/wiki/ [open-mesh.org]

      Also, the torrent protocol offers parts of the solution: everyone stores a small part of the addresses. Which part to store is determined by the unique 128-bit number you've chosen. So even if everyone just knows how to get a little bit closer to the data/address you're looking for, that's good enough. A few query/response iterations should give you what you're looking for.

    • I'd hope to introduce a CAN element, running in parallel - it's far more efficient than the usual packet-switching approach for disseminating data, fault-tolerant, censor-resistant and neither source nor destination nodes even need an address. You'd still need a conventional network too, but with CAN handling the big transfers of images and video you have a lot more resources available for your IP traffic. The two approaches compliment each other.

      As for addressing, I wonder if geography can help? Give each

    • by Myself ( 57572 ) on Friday June 07, 2013 @01:01PM (#43938103) Journal

      While much of Manhattan's traditional communications infrastructure was literally a smoking crater after 9/11, the Ricochet mesh network was alive and well, built to barely notice the loss of individual nodes.

      The company had recently gone bankrupt, but all the hardware was still in place, so some ex-employees drove [archive.org] from Denver to NYC with a bunch of modems and laptops, to bring mobile connectivity to the recovery effort.

      Mesh works in this case because MCDN uses geographic routing [wikispaces.com] -- the packet header literally contains a packed lat/long for the destination, and nodes make their routing decisions by angle and distance. There's a layer of name-to-geo resolution which makes that all work, and in the Ricochet days it was centralized, but I believe it could be made to operate with DHT like torrent networks do now.

    • by sjames ( 1099 )

      Yes, big ARP tables. It's not as bad as you might think, though some of the anemic devices out there now could never handle it. For example, assuming you have <256 directly visible peers that can route, a table for an IPv4 sizd address space is only 4GB. Allow 8GB if you have 64K direct peers.

    • Broadcast it, like plain old radio. And then we tune in. However has the matching half can decrypt it.

  • by perpenso ( 1613749 ) on Friday June 07, 2013 @11:54AM (#43937095)
    Philosophically the emergency ad hoc network sounds like ham radio, individuals volunteering their time and/or equipment to help their community during disasters. It might help to mention this when trying to sell the idea to analog folks.
    • There's actually an amateur radio project to create a mesh network, as WiFi channels 1-6 actually fall into the ham bands. It's not very widespread in that you can just set up a node and get on, but it is pretty easy to deploy at events or in emergencies - just take the router out and plug it in. The site is hsmm-mesh.org [hsmm-mesh.org].

  • As long as they can keep the fucking government out of it, I'm all for it.
  • The problem I can see with it is the governments in question will simply start actively jamming or disrupting these frequencies if they think they're being used to subvert the systems they're trying to monitor.

    To do this properly, I think you might have to resort to a system that randomly changes frequencies as it runs -- so modified hardware would be needed as well as software?

    • by mspohr ( 589790 )

      Let's see... these networks run over WiFi frequencies.
      You could jam all WiFi frequencies but that would be:
      a) non-trivial
      b) obvious
      c) self defeating
      d) all of the above

    • The more extreme they are forced to go in censorship, the more the backlash they will provoke. Even the people will no interest in politics are going to get annoyed when the government jams their garage door opener and the keyless entry on their car.

  • by H310iSe ( 249662 ) on Friday June 07, 2013 @12:13PM (#43937333)
    Open Garden [opengarden.com] - I tried version pre v1.0 during anonymous protests of wifi shutdowns on public trans. and it was not working very well (at all) but they're at v 2.0 now from the website: "Seamless connectivity allows people to connect any supported device to the mesh and thus to the Internet with no effort or configuration... introducing a way to access the Internet over multiple paths at once, improving speed and reliability... Once connected, devices find a path to the Internet also completely automatically. If a path fails, a new one will be chosen; if necessary, new connections will be established. The network is self-healing and self-forming. Each of the nodes operates only with local knowledge; together, they build a network using a probabilistic distributed algorithm."
  • "There should be easy practices for anyone to open up an otherwise-closed Wi-Fi access point if it's still connected to broadband and is near people in trouble"

    That sounds like an open invitation for every hacker in the world to open up any Wi-Fi access point. How can you guarantee that such a capability wouldn't be abused?

    • by nhat11 ( 1608159 )

      Hackers ruin everything =(

    • "There should be easy practices for anyone to open up an otherwise-closed Wi-Fi access point if it's still connected to broadband and is near people in trouble"

      That sounds like an open invitation for every hacker in the world to open up any Wi-Fi access point. How can you guarantee that such a capability wouldn't be abused?

      I assume it would be just like making any other change to your browser through the configuration webpage.

  • Former FCC Chairman Julius Genachowski has had since September 2012 to respond to my complaint about GoogleFiber joining the "any kind of server prohibited to residential ISP internet users". His administration at the FCC refused to give me in all this time, a single sentence explaining to me whether they agreed with any or all of my complaint that started as a sub-1000 character 2000F complaint, and evolved to a 53 page small font dead tree document delivered by the office of my state's Attorney General a

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