Sending Data In Bursts of SMS Messages

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."

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

[Joe The Dragon]

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

My Sprint service isn't reliable

[Anonymous Coward]

and I'm in a major US city. it sucks when it's commonplace to get text messages out of order. Sometimes I'll get one that was sent several hours earlier.

Unusable and expensive

[clone53421]

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

How truely AWFUL...

[nweaver]

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 [smsanalysis.org]:

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.

Huh?

[Monkeedude1212]

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? [worldbank.org]

Calling smart people

[Applekid]

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.

Wrong solution

[maxrate]

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.

Re:My 300 baud modem shivered...

[Anonymous Coward]

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

Re:Calling smart people

[Pentium100]

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

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

[geekpowa]

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.

Worst. Transport. Ever.

[straponego]

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?

Re:My 300 baud modem shivered...

[xaxa]

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

What about GPRS?

[AC-x]

> 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

Re:Calling smart people

[sznupi]

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.

Re:Wrong solution

[colinnwn]

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.

Affordable?

[damn_registrars]

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.

Re:Worst. Transport. Ever.

[fuzzyfuzzyfungus]

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....

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

[Peach Rings]

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

Re:Oops

[sortius_nod]

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.

Re:Oops

[newcastlejon]

...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.

Re:Calling smart people

[petermgreen]

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.