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Sending Data In Bursts of SMS Messages

Posted by timothy on from the out-of-band-and-back-again dept.

An anonymous reader writes "Canadian carrier Rogers has been experiencing some extreme loads of late, as researchers at the University of Waterloo investigate the potential for sending data spread across bursts of hundreds of text messages. They sent around 80,000 messages in the course of a project testing a new protocol able to cram 32KB into 250 messages sent from a BlackBerry, reaching a rate of 20 bytes per second. The group thinks its protocol could be useful in rural areas of the developing world where text messaging is the only affordable, reliable link."

42 of 181 comments (clear)

  1. Oops by ekgringo · · Score: 5, Funny

    Make sure you get the "unlimited" text messaging plan before trying this...

    1. Re:Oops by sortius_nod · · Score: 2, Insightful

      Yeh, I really don't get it myself.

      Quick calculations, your average 1hr TV show would end up costing you around $500 000 if you didn't have a cap.

      Why even research this technology? It's not like we weren't aware that SMS was capable of this, it is text after all. I see nothing of value in this research, I'm sure that someone with a bit of coding skills and access to a mobile could do this without much hassle.

      I'm usually the first to say to people on slashdot that research is worthwhile, but this is really stupid. This won't do anything to relieve congestion at all, it will just shift it to SMSing. So your SMS to your loved one saying you'll be home 15 minutes late will arrive in a few hours.

    2. Re:Oops by TheRaven64 · · Score: 5, Informative

      It's completely idiotic. There are two ways in which SMS is implemented:

      On older GSM networks, it's part of the control channel. There is some unused space in one of the control packets. It was a scarce resource and flooding it could actually prevent anyone making calls (there was a fairly simple DoS attack possible). This was the original reason for SMS being expensive - the network couldn't handle much SMS traffic.

      On newer networks (GPRS and newer), it's just treated as data. It's wrapped in a packet header indicating that it's SMS and then sent in the same way as IP data.

      In any area where you just have GSM, there isn't enough bandwidth available for SMS for this to be useful. In an area where you have GPRS or anything newer then SMS is just a way of adding a huge packet header to your IP packets. It's transmitted the same way as IP data, you're just using the available bandwidth less efficiently.

      --
      I am TheRaven on Soylent News
    3. Re:Oops by newcastlejon · · Score: 3, Insightful

      ...In any area where you just have GSM, there isn't enough bandwidth available for SMS for this to be useful.

      In these circumstances CSD is probably available too at a heady (in comparison) 9.6kbps.

      --
      If God forks the Universe every time you roll a die, he'd better have a damned good memory.
  2. so now will they bill $1 per txt each way? by Joe+The+Dragon · · Score: 2, Insightful

    so now will they bill $1 per txt each way?

    1. Re:so now will they bill $1 per txt each way? by geekpowa · · Score: 4, Insightful

      In emerging economies SMS is dirt cheap. In Philippines: $0.50, 24 hour all you can eat (on-net only) deals are common.

      This is a bad idea for a large number of technical reasons : very inefficient use of the GSM channel because of all of the excessive handshaking and control just to transmit a 140 byte data packet for one (sms is 7bit per character. 160 chars = 140bytes) and rubbish throughput & latency. But economically it makes sense. Also accessibility of 2G mobile phones is very high in such environments, 3G wireless or twisted pair copper not so much. Depends where you deploy it, for what eventual purpose and actual real bandwidth requirements.

    2. Re:so now will they bill $1 per txt each way? by fuzzyfuzzyfungus · · Score: 3, Informative

      It's an especially terrible plan, if widely adopted, because SMS comes out of the control channel. If you have enough SMS traffic flying around, the carrier will either have to start dropping it, or have plenty of available voice/data channel lying idle because they don't have enough control channel capacity to set up and tear down calls.

      Obviously the poor people in the sticks might not have fancy 3G stuff; but why would you attempt to shove data over SMS(aside from short message snippets from embedded devices, and suchlike applications), when GPRS already exists? All sorts of dirt cheap phones support being used as modems, without any special software, and, while it might well be more expensive now, for economically perverse reasons, SMS won't be cheaper for long if it becomes standard practice to do general-purpose data transfer over SMS on a large scale...

    3. Re:so now will they bill $1 per txt each way? by Peach+Rings · · Score: 5, Insightful

      Maybe they should just make normal data transfer reasonably priced instead of jacking up SMS pricing...

  3. My 300 baud modem shivered... by Overzeetop · · Score: 5, Funny

    ...and got to feel the thrill of competition again.

    --
    Is it just my observation, or are there way too many stupid people in the world?
    1. Re:My 300 baud modem shivered... by Anonymous Coward · · Score: 2, Insightful

      Yeah, how backwards is this text method? Put the phone on one of those old modems al la Wargames and send data like it's 1989!

    2. Re:My 300 baud modem shivered... by Nethead · · Score: 2, Informative

      You must be young. I remember using acoustical modems back in 1974 and they weren't that new back then. The reason we used them was because it was illegal to connect to the copper on a POTS line back then and Ma Bell's solution was VERY expensive and very non-portable.

      --
      -- I have a private email server in my basement.
    3. Re:My 300 baud modem shivered... by xaxa · · Score: 2, Insightful

      ...or just buy the data cable (or USB cable, if your phone uses USB) and download the modem drivers.

    4. Re:My 300 baud modem shivered... by Anonymous Coward · · Score: 3, Funny

      So the clear answer is voice-over-ip-over-sms

    5. Re:My 300 baud modem shivered... by bill_mcgonigle · · Score: 4, Interesting

      I remember using acoustical modems back in 1974 and they weren't that new back then

      I've actually considered seeing if I could get a v.32 in-software stack to communicate over the bluetooth headset/microphone protocol so I could do very basic data networking over a cell phone without a data plan. Like ssh.

      I came to my senses, but I kinda still want to try it anyway.

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    6. Re:My 300 baud modem shivered... by pyrrhonist · · Score: 2, Informative

      The reason we used them was because it was illegal to connect to the copper on a POTS line back

      That became legal in 1968 with the Carterphone ruling. You probably had an acoustic coupler in 1974, because the modular jack wasn't introduced until 1976.

      --
      Show me on the doll where his noodly appendage touched you.
    7. Re:My 300 baud modem shivered... by tepples · · Score: 4, Interesting

      The lossy compression used in digital cellular telephony has a smearing effect that screws with the rapid phase transitions used by quadrature amplitude modulation. You aren't going to get a lot of bits per second out of digital voice.

    8. Re:My 300 baud modem shivered... by jimmydevice · · Score: 2, Interesting

      At 110/300 Baud, you did a lot of mental pre-processing of your requests.
      Listing out hundreds of lines (unless you were getting a listing) was
      not the way to go.
      Vi runs OK at 1200 baud on a 24X80 display, If you know that you're
      looking for.

  4. Unusable and expensive by clone53421 · · Score: 2, Insightful

    You pay: Monthly for a cellular package with unlimited texting
    You get: 20 baud

    --
    Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
    1. Re:Unusable and expensive by schon · · Score: 3, Informative

      You pay: Monthly for a cellular package with unlimited texting
      You get: 20 baud

      Actually, (ignoring the fact that "baud" is the incorrect term) that would be either 160 or 200 baud, depending on whether you include error correction bits in the calculation. :)

  5. Big money, no wammies by Itninja · · Score: 4, Funny

    In a completely unrelated story, the University of Waterloo has an unexpected ~$16,000 shortfall this quarter.

    --
    I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
  6. How truely AWFUL... by nweaver · · Score: 4, Insightful

    Text messages are one of the most awful forms of data on the cell network. On a 3G type network, they are just data, so hey, if you can do TXT on 3G, just do data. So what?

    But on older networks, such as the proposed usage, they take up CONTROL channel space, and too much SMS is a DOS attack!

    See Exploiting Open Functionality in SMS-Capable Cellular Networks:

    ABSTRACT: Cellular networks are a critical component of the economic and social infrastructures in which we live. In addition to voice services, these networks deliver alphanumeric text messages to the vast majority of wireless subscribers. To encourage the expansion of this new service, telecommunications companies offer connections between their networks and the Internet. The ramifications of such connections, however, have not been fully recognized. In this paper, we evaluate the security impact of the SMS interface on the availability of the cellular phone network. Specifically, we demonstrate the ability to deny voice service to cities the size of Washington D.C. and Manhattan with little more than a cable modem. Moreover, attacks targeting the entire United States are feasible with resources available to medium-sized zombie networks. This analysis begins with an exploration of the structure of cellular networks. We then characterize network behavior and explore a number of reconnaissance techniques aimed at effectively targeting attacks on these systems. We conclude by discussing countermeasures that mitigate or eliminate the threats introduced by these attacks.

    --
    Test your net with Netalyzr
  7. Huh? by Monkeedude1212 · · Score: 2, Insightful

    They couldn't have built their own network and emulated phones to test this protocol, they had to go live with their phone provider? Some University. I bet MIT is laughing out loud.

    Also, how's the coverage out there?

  8. Calling smart people by Applekid · · Score: 3, Insightful

    Anyone care to describe why they couldn't just use airtime minutes and an acoustically coupled modem? Looking it up on Wiki, in general they were able to transfer 300 bps instead of 160.

    --
    More Twoson than Cupertino
    1. Re:Calling smart people by Pentium100 · · Score: 2, Insightful

      Or just use a phone that has a modem, most of new ones do, IIRC you can get a few kilobits with it.

    2. Re:Calling smart people by sznupi · · Score: 2, Insightful

      What they're doing is just an awkward, slow and very limited way of what WAP was doing over a decade ago, also via channels used for SMS.

      --
      One that hath name thou can not otter
    3. Re:Calling smart people by petermgreen · · Score: 2, Insightful

      I thought most phones that could talk to a PC could at least do an old fassioned GSM data call (which is very slow by modern standards but still fast comared to this).

      A friend of mine has an old HP dos based PDA which has a socket in the back for a nokia 2110 and we managed to get it to dial up an ISP and access email.

      --
      note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
  9. Wrong solution by maxrate · · Score: 3, Insightful

    Not trying to troll, but this is the wrong 'solution' for so many reasons. If SMS's can make the connection, so can other forms of packet radio.

    1. Re:Wrong solution by colinnwn · · Score: 2, Insightful

      It's sub-optimal, but not necessarily the "wrong solution". Rather than setting up your own packet radio network, this allows you to piggyback on existing infrastructure for the cost of a mini-USB cable and unlimited txt plan. There may be some valid uses.

  10. Re:Why bother? by EricJ2190 · · Score: 4, Funny

    If it's anything else, drive to Starbucks for free wifi.

    Because Starbucks is so commonplace in the "rural areas of the developing world."

  11. Re:My Sprint service isn't reliable by JWSmythe · · Score: 2, Interesting

        I was going to bring that up. I frequently see out of order messages on quite a few providers, in various locations (major cities around the US and Canada). I had a server monitoring the rest of my servers. It would send timestamped messages when there was a problem status. In the event of a big problem, it would send a whole flurry of them. When your pager goes nuts, you know it's something major that needs your undivided attention immediately. Most would arrive on time. Sometimes messages would show up out of order, or hours late. It's scary when you think the whole issue has been resolved, and then you get another "down" page an hour or so later. That's why we timestamped them, so we'd know if it was just late showing up.

       

    --
    Serious? Seriousness is well above my pay grade.
  12. This is Tailor-Made for... by srmalloy · · Score: 4, Funny

    ... next year's April 1 RFC -- "IP over SMS Carrier".

  13. Re:Why??..... by GNUALMAFUERTE · · Score: 4, Interesting

    I think this is more a case of "Look mama, IP over SMS! With No hands!" than a solution for any real world problem.

    --
    WTF am I doing replying to an AC at 5 A.M on a Friday night?
  14. Neato! by zmollusc · · Score: 5, Funny

    This is good news (everyone), by the time you have torrented your bluray rip, it will be out of copyright.
    Or not.

    --
    They whose government reduces their essential liberties for temporary security, receive neither liberty nor security.
    1. Re:Neato! by VMaN · · Score: 2, Interesting

      At 601.90 MB per gregorian year, that's not so far off...

  15. Worst. Transport. Ever. by straponego · · Score: 2, Insightful

    I'll mostly leave it to others to enumerate the many flaws in this, except to note that under AT&T I often had text messages arrive hours or days late, or never. But I do have to applaud this group. This is, by a wide margin, the worst idea I have ever seen in a /. story. Are we sure this wasn't a belated April Fool's gag?

  16. What about GPRS? by AC-x · · Score: 2, Insightful

    > The group think their protocol could be useful in rural areas of the developing world where text messaging is the only affordable, reliable link

    It's a fun little project, but in what circumstance would this *ever* be the best use of a mobile network? If you've got the signal for SMS then you should be able to also at least use a voice call to transmit data (not sure what the max would be, 14.4kbps? 9.6kbps?) if not full GPRS (56-114 kbps). 160bps is not very impressive

  17. Yak Protocol by Ukab+the+Great · · Score: 5, Funny

    Maximum carrying load of a Yak: 70kg
    Weight of a 32GB micro sd card. 0.5g
    Having your own 3rd world petabit network: priceless.

    1. Re:Yak Protocol by BuckaBooBob · · Score: 2, Funny

      This like WiFi degrades significantly with distance..

      Doing some rough math.. A Yak that can go 5km/hour when fully loaded using your numbers can Transter about 25 Peta-bytes per second over 1 Meter... at 25 Meters your down to 1 Peta-byte/s.. This is Payload Only.. It does not include packing or transferring information on and off the SD's. The Latency would be extremely high... I am gussing that the Protocols that have been developed for data transmissions to the Moon might still not have enough forgiveness to hand the latency of this.

      --
      Who needs WiFi when we can have Packet Over Sheep! http://datacomm.org/PoS-InternetDraft.txt
  18. What do you mean? by colinnwn · · Score: 3, Funny

    I have to pay $10 when I text "HAITI" to 90999! I thought Microsoft was paying.

  19. Affordable? by damn_registrars · · Score: 2, Insightful

    Really? Do these people not have a postal service? Per unit data a stamp is many orders of magnitude less expensive for sending data than a text message.

    --
    Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
  20. Re:Worst. Transport. Ever. by fuzzyfuzzyfungus · · Score: 2, Insightful

    Never is, of course, a serious issue; but hours or days late would be solvable with the right protocol.

    Bittorrent, in effect, deals with rather similar issues(since it is typically used to transfer files so large that they make common home internet connections feel like ghastly retro shit) reasonably effectively. It may take a while; but sufficient patience will get you past any number of corrupted blocks, dropped packets, hosts that disconnect, etc.

    Any sort of latency-sensitive application will be right out the window; but dumping blocks of data from point A to ghastly-end-of-the-earth B should be totally doable....

  21. Very old hat trick - This existed before by williamyf · · Score: 2, Interesting

    Remember WAP?

    The WAP service had three posible bearers, GPRS (the best for it), a circuit switched dedicated 9600bps link (later upgraded to 14.4kbps, or even 56kbps), or SMS.

    Well yes, in WAP times there was a full spec on how to transport data on lowly SMS. As other posters have said, using SMS as a bearer for other data services is painfull, slow, ackward, and not such a good idea.

    Ah, this brings memories!

    http://www.m-indya.com/wap/wap_bearers.htm

    --
    *** Suerte a todos y Feliz dia!