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Networking Technology

DARPA Wants Huge Holy Grail of Mobile Ad Hoc Networks 61

coondoggie writes "Even the often far-reaching researchers at Defense Advanced Research Projects Agency (DARPA) seems to think this one is a stretch: Develop what's known as mobile ad-hoc wireless technology that lets 1000-5000 nodes connect simultaneously and securely in the field. For the past 20 years, researchers have unsuccessfully used Internet-based concepts in attempts to significantly scale mobile ad hoc networks, DARPA said. A constraint with current examples is they can only scale to around 50 nodes before network services become ineffective."
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DARPA Wants Huge Holy Grail of Mobile Ad Hoc Networks

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  • by smittyoneeach ( 243267 ) * on Tuesday April 30, 2013 @05:56PM (#43596003) Homepage Journal
    Your network's hairy
    Your servers are duds
    Only one way to shave it
    And that's drown it in suds!
    Burma Shave
  • i though of this years ago. probably a decade ago. there is no packet enveloping. the header is fixed length:
    [source address][destination address][time initially sent][time from last hop]
    the clocks on the units must be synced highly accurately, but there's a way to do that democratically over the same channels, using unused bandwidth. also unused bandwith can be used to exchange hash data to optimize routes.
    then the thing you want to figure out, at each point, is, given the destination address, what "po

    • now the next level to this, for mobile ad-hoc networks, would be using gps data as a pre-fix to the "source" and "destination" address, and if it can't find the actual device, it routes to the known destination with that reduces the gps distance at the greatest rate. then it really becomes a path-finding algorithm with obstacles.

    • data structures would be kind of like this:

      neighboring_devices table:
      [neighboring_device][last_gps_coordinate][last_connected][single_hop_recieve_lag][single_hop_send_lag][last_recieved_time][last_sent_time][packets_recieved][packets_sent]

      communicating_devices table:
      [communicating_device][last_gps_coordinate][total_recieve_lag][total_send_lag][last_recieved_time][last_sent_time][packets_recieved][packets_sent]

      route_stats table:
      [communicating_device][neighboring_device][total_recieve_lag][total_send_lag][las

  • If the transmitter scaled its output power to connect with the closest neighbors without saturating the far field.
    Use forwarding and only increase power when QOS was not maintained. Maybe?

  • I wonder how many homes are on one 'collector': bchydro [bchydro.com]
  • by tlambert ( 566799 ) on Tuesday April 30, 2013 @08:27PM (#43596939)

    This problem is more or less solved already. It can be done through ad hoc mesh networking, and there is firmware that can be used on Atheros and several other vendors chips.

    The problem with deploying any of this is that the ability to do this with civilian devices disintermediates the cell phone user from the cell network providers. So there are huge buckets of money which Do No Want This Firmware Available Anywhere. Deploy it, and you mostly do not need cellular carriers, unless you need lower-than-voice-acceptable latency on your network for higher speed data (e.g. multiplayer video games).

    The half a dozen companies that can already do this include Google; I used to sit about 200 feet from the office of the primary researcher.

    • by Anonymous Coward

      So... what's the firmware? No need to keep it a secret.

      • So... what's the firmware? No need to keep it a secret.

        The firmware which has been developed in house by each of these companies, and which is not available because the WNIC vendors would have to submit the firmware and hardware as a unit to the FCC for certification as an SDR (Software Defined Radio). As such, it would be a violation of both the WNIC vendor license agreements and the FCC regulations were it to be distributed. The first loses you your relationship with the WNIC vendor, the second gets you fined at best and thrown in Federal Prison at worst.

        If

    • by Anonymous Coward

      Google don't even want to enable ad-hoc wifi in Android... https://code.google.com/p/android/issues/detail?id=82 .. but it can be added if you are willing to install a modified cyanogenmod: http://www.thinktube.com/android-tech/46-android-wifi-ibss

      • Google don't even want to enable ad-hoc wifi in Android... https://code.google.com/p/android/issues/detail?id=82 [google.com] .. but it can be added if you are willing to install a modified cyanogenmod: http://www.thinktube.com/android-tech/46-android-wifi-ibss [thinktube.com]

        Google has zero control ver Android-based product productization. All those decisions are made by the device vendor during the final productization phase by the partner (read: device vendor). This is also why there are so many versions of Android out there; each device has its own Android variant based on the exact state of the source tree at the time they did a local replica in order to start the productization phase.

        If Google moved productization in-house, they could cause a more uniform environment for

        • Google has zero control ver Android-based product productization.

          While that's true, they set defaults. Why is there still no pinless pairing in Android 4.2? You have to use an app for that, a non-localized app only in Japanese and with a minimum of icons. At least it's free... Ad Hoc networking should be included by default, too. They can't stop carriers from turning it off, but they can provide it.

          • Why is there still no pinless pairing in Android 4.2?

            Does that mean something different than not needing a PIN to pair? I just paired my wife's Motorola Froyo phone with a headset last night and it didn't need a PIN.

            • Does that mean something different than not needing a PIN to pair? I just paired my wife's Motorola Froyo phone with a headset last night and it didn't need a PIN.

              Some vendors have implemented their own solutions to this problem, especially for headsets, and especially for their headsets. But no, that's all it means. For example, try pairing a PS3 remote.

    • Because the people at DARPA haven't heard of, or seen any of that!

  • How about a bunch of nodes share the same IP address, but the data they receive has a precursor integer to tell who gets it, or maybe a different port. You'd get a bunch of garbage information you don't need, but that garbage information is someone else's data.

    Then the problem just comes down to how much bandwidth you have. And you gotta be cool with people not snooping you data. Do you even encrypt?
  • includes broadcast

    basically you need to figure out the phy/eth portion of the network not the software side

    so if you can do SDN/Software defined radio and come up with a nice way to scale then your good

    I would have thought that zigbee / sensor networks would already scale you just have to boost range but hey thats me just guessing

    regards

    John Jones

  • by Areyoukiddingme ( 1289470 ) on Tuesday April 30, 2013 @10:33PM (#43597591)

    "This could provide more troops with robust services such as real-time video imagery, enhanced situational awareness and other services that we have not yet imagined."

    Uhm. Yeah. There's your problem. Video imagery? Dream on. No, you are not going to get a unique video stream into and out of every single one of 5000 ad hoc wireless network nodes functioning in a mesh. It's stupid even to consider the idea. And no amount of protocol fudgery is going to fix that. The bandwidth simply isn't there in the hardware.

    Could all 5000 nodes connect to an IRC server and provide text chat? Yup. With great reliability. I guarantee that would work flawlessly. And you also wouldn't want to do that either. Ever been in an IRC channel with 100 active users? I have. It's bedlam. Readable, if you're REALLY paying attention, and read quickly, but still bedlam. 1000-5000? Useless. Especially when you're busy trying to avoid getting shot. But it would work. So divvy up the people into individual channels for companies, platoons, squads, and fire teams, and now everybody has a reasonable amount of information to keep track of. And everybody's dead. 'cause if you thought trying to text and drive was hazardous...

    So here's the thing. What do they really want to do with it? The phrase "enhanced situational awareness" is probably the only really useful thing in that quote. If I was out trying to avoid getting shot, knowing ahead of time where people are who are likely to shoot me seems like the most valuable thing. And that isn't a machine to machine communications problem. That's a man to machine and machine to man communications problem. Mostly it's a man to man mediated by machine communications problem, and I have a feeling if you asked any marine what he wants most, his answer is going to be "make sure my voice radio always always works." 'cause that's the standard any "enhanced situational awareness" has to exceed. Not meet. Exceed.

    And that, ladies and gentlemen, is a human-computer interface problem, not a networking problem.

    • No, you are not going to get a unique video stream into and out of every single one of 5000 ad hoc wireless network nodes functioning in a mesh. It's stupid even to consider the idea. And no amount of protocol fudgery is going to fix that. The bandwidth simply isn't there in the hardware.

      Are you sure you can't theoretically carry 5,000 low-resolution video streams on such a network? With all nodes arranged in a line, of course you couldn't. But with multiple points of egress? You're just making things up, you have no idea what such a network might carry.

  • Routers.. simple. (Score:4, Insightful)

    by aaronb1138 ( 2035478 ) on Tuesday April 30, 2013 @11:02PM (#43597707)
    For the kind of bandwidth and performance they want, dedicated routers are needed. A pure ad-hoc setup won't work. The network can be self configuring in an ad-hoc like fashion, with routers acting as supernodes and preferably sending some control data for channel / geographic setup and configuration updates.

    Being that this is DARPA, they need to talk to their DOD peers who have solved logistics equations and simulations. You don't send 50+ troops into the field all at equal rank together. You have some sergeants and lieutenants to coordinate command and control. Same thing with a mesh building ad-hoc router. Heck, the math side should work out almost exactly the same for number of equipment tiers and number of equipment pieces at each tiers as for troops in the field.
  • they should talk to the Serval project people

    http://www.servalproject.org/ [servalproject.org]
  • It's designed to do so, and has proven itself in wireless community mesh networks.

  • DARPA is not new to this: http://www.bbn.com/technology/networking/wnan [bbn.com]

    You guys suggesting ridiculously simple approaches don't do this problem justice. Dynamic Spectrum Access, MIMO, Multicast VOIP, and amazing routing smarts, it's all there. There's some crazy-smart people behind WNaN, and it scales beautifully. At the 102-node experiment in 2010, network services were far from "ineffective". I suspect that much larger MANETs would work fine, even with this already-built radio system. The summary doesn
  • by Anonymous Coward

    A lot of the comments seem to be sort of ignoring what DARPA is trying to do. If you look at ARPAnet, it was designed as a failure tolerant communications network (a mesh, of all things) using "wired" connections, but with a semi-hierachical topology.

    Meshes work and exist but for low data rates and fairly small numbers of nodes (tens or hundreds, not thousands)
    "The Internet" is basically ARPAnet all grown up, but is hierachical, and has very high value targets (backbone routers, etc.. MAEwest goes out and

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