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Jamming Cellphones with Text Messages
Steve writes "Some Penn State professors and students have published a way to jam cellular voice service with simple text messages. From the article: 'Because text messages are transmitted on the same signal that is used to set up voice calls, just 165 messages a second is enough to disrupt all cellphones in Manhattan.' Cellular providers, of course, fired back, one stating that it 'constantly and aggressively monitors potential threats to the integrity and security of its network.'"
Magic Link, hopefully without a session id.
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http://www.nytimes.com/2005/10/05/technology/05ph
_JS
A more detailed description of the threat is at smsanalysis.org/. The actual paper at smsanalysis.org/smsanalysis.pdf.
$990/minute, assuming a charge of 10 cents per message.
Most people don't know that you can send text messages for free through Google's text messaging service.
... hello? ...hello?
http://toolbar.google.com/send/sms/index.php
Now all you need is a perl script and
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judge a man by his wallet
------ The best brain training is now totally free : )
Can you say Copy and Paste Troll?
Facts do not cease to exist because they are ignored.
Do you have a source?
There must be at least a million cellphones in Manhattan. I'd say its safe to say that each cellphone would send an average of one text message a day.
So there are already somewhere in the rough ballpark of 1 million text messsages being sent a day. Possibly many more, probably no less.
that equates to 41,000 per hour, or 72 per second, on average.
Now of course the texts aren't spread evenly over those 24 hours. The majority of those messages will be sent during 12 hours of the day, which would mean during those 12 hours the average texts/second would be pretty close to the number of texts they say would overload the network.
sending smsm messages uses the control channel, which is required for setting up each voice call. ever noticed sometimes you can send/recv SMS messages but when you try to call you get no service
Snowden and Manning are heroes.
I'm sure there are at least 165 text messages being sent every second already.
Yes I do know there are store and forwarding to consider/routing etc, however I find this unlikely.
true, and if other providers are like cingular, you can just write a script to go through a given range of telephone prefixes. with cingular, an email to 1231231234@my.cingular.com will result in a text message being sent to 123-123-1234's cell phone.
-William
God is everything science has yet to explain.
.... with Verizon's *in* network, $5 a month flat rate to other Verizon members.
Verizon kicks ass.
-everphilski-
I know from connections to several european 'short message service centers' that they won't accept more then 10 or 100 messages a second even for wholesale connections (content providers, chat providers, tv games etc.). The overal capacity can never overflow the network since there is a limiter on the SMSC.
jouwnieuws!
You can email a text message to someone's phone, and for some carriers it is an automatic $0.10 or more a message received and the reciever can't not recieve it. Here are all the SMS addys:
Sprint: 10-digit-number@messaging.sprintpcs.com
Verizon: 10-digit-nmber@vtext.com
AT&T: 10-digit-number@mobile.att.net
T Mobile: 10-digit-number@tmomail.net
Nextel: 10-digit-number@messaging.nextel.com
Cingular: 10-digit-number@mobile.mycingular.net
Alltel: 10-digit-number@message.alltel.com
i can see how they could put in safe-guards like monitoring multiple messages from an IP in a certain time frame. but, smart programmers can work around this fairly easily.
a couple reasons... bandwith available is very limited. the entire licensed spectrum for cell phone coverage is less than the frequency a single analog TV broadcaster uses.
so yeah data is expensive, and frankly the answer to that was going to be the FCC taking all 13 channels of VHF broadcast and converting them to various products including a large subset to be licensed for cellular broadcasts... but the states is nowhere near the numbers that would allow the FCC to license off those frequencies.
if you have more frequency you can sell 'data' for less. they've already gotten to the point where voice calls are unlimited on weekends and evenings, so they can get virtually everyone paying $40 a month for service they can only realistically use during the day when it takes off plan minutes/really costs money.
https://www.gnu.org/philosophy/free-sw.html
While it is technically feasible that this could be done, implementing an anti-spam filter, or similar, on the mail address in question. While everything is still going through a server (and I'm sure similar solutions can/will exist for SMS), whether it's email or SMS, I'm pretty confident that a modern IDS could already help if someone tried to do this by emailing a phone.
I don't moderate anymore. Karma penalty for 90% fair mods? Can I mod that unfair?
Let's look at it this way:
Sources of Bandwidth/Attacks
The original article assumes you wanted to take out more than one sector in the cellular coverage. If you wanted to be more specific and pinpoint only a handful of sectors, you would need less than the numbers the article specifies.
Most text messaging service providers have email gateways. This is one of the reasons why I disabled my text messaging capability. No way to filter the message and at $0.10 / message, it is too abusable.
A weak computer running a fast multi-threaded emailer(Postfix) can dump a fair amount of email at a email-to-sms gateway. It is amazing how many messages/sec you can achieve if you tweak your configuration. 3-4 well placed and configured systems could take out a sector or 2. Distribute that over 10-20 thousand zombies, and you have much greater capacity and better redundancy. The provier will either need to already have anti-DDOS equipment in place or shut down the gateway. Bounce those over open relays and it makes dynamic rerouting even more difficult.
Scenario:
There is a convention going on. Someone was going to launch an attack on the convention site. They don't need to wipe out access to the entire city. They only need to wipe out acccess to the cellualr cells/sectors covering the convention area itself.
So, they gain access to a list of peoples' phone numbers, who will be attending and SMS-bombard those numbers.
Guess what? Since all of those numbers are at the convention site and being serviced by a fixed number of cellular cells, you have now effectively targetted those cells and overloaded them.
With the cell access busy, to the people trying to make calls or receive calls at the convention, an attack on the convention would only be reportable by landline and/or by bystanders outside of the convention center.
Say the attack is a silent one: chemical, toxin, biological. The emergency response would be delayed enough that most of the target individuals would be dead before help could arrive. Most people these days depend heavily on their cell phones. The first thought isn't to try to make a call on a landline for many.
Another abuse would be to use the system to financially deplete another organization's funds by ramping up their telco fees through excessive messaging via a zombie network. While most organizations might have flat fee subscriptions, some do not. Especially for their one-off need-it-now celphone plans.
I've actually called my provider and asked them about filtering and blocking, but they have told me that it was either completely on or completely off. I chose completely off.
Winged Power Photography
For those of you who have never looked at a real phone network, allow me some bandwidth:
Nobody has ever allowed for a one to one switching network like you may have seen with a switched hub. It's too expensive. They use trunk lines instead. The number of trunk lines depends on the statistics of the local area calling. There are benchmarks to use for various types of service. These systems are designed for four and five nines of up time. But it's not overload proof. You have all gotten fast busy signals before. That's because there were no trunks available.
What these folks have figured out is how much bandwidth a typical cell site can have. They have figured out how many text messages it would take to fill up that available bandwidth. Big Deal. Cell sites do saturate. This is not a design "flaw" --it's a design point. Just as almost nobody builds buildings to withstand 200 MPH winds, almost nobody builds that much bandwidth in to a cell site. You could, but it would almost never get used.
Instead we build them to handle almost all conditions. Yes, they can saturate. That's a political design issue. Someone who knows the design points can certainly overload one. But during normal use, they will work just fine. Since there are no lasting effects from such overload, most engineers figure that people will just clear out before things get too dicey.
Naturally, some twits who want to jam cell phone conversations will find plenty of ways to do this. The network is built for civil use --not military use. That's why police and fire authorities use seperate communications networks (or if they don't they're just asking for trouble). That's why ham radio operators are often able to render assistance when everyone else is busy trying to call home. Common Carrier networks will overload at some point, just as roads can saturate and slow to a crawl. We'll never have enough bandwidth or enough roads. But we can ensure that there will be enough to get by.
The Times could do for a brief lesson in engineering design criteria...
Nearly fifty percent of all graduates come from the bottom half of the class!
Over here in Australia, on New Years eve, the entire network is brought to it's knees. I assume there are not only bandwidth issues with the local spectrum provided, but also between cells or with the central aggregation point.
Using your cell phone pretty much within 30 minutes either side of Midnight is practically impossible, unless you have very good patience - and that's only to send a text message, a phone call is like asking jesus to appear for you. It seems to get worse every year, as usage gets higher and higher. And messages often take hours to be delivered, I received half a dozen messages, scattered between about 2 30 am and 4 30 am on the 1st of January this year, all sent at 12:00:xx.
I forgot to mention, I live in a small town (probably 2 000 or so people), served by atleast half a dozen cells (well, half a dozen are available with good signal quality, with the one dedicated to us being visible all through town and often from remote locations as our town is slightly risen)
I've always wondered why when watching the countdown on TV (Regular free-to-air) the video feed usually distorts fairly noticeably as soon as the new year is it - like interference.. What could that be?