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Boston Officials Did Not Shut Down Cell Network After Marathon Bombing
An anonymous reader writes with this excerpt from Motherboard about the immediate aftermath of yesterday's bomb attack in Boston, which attempts to explain the (unsurprisingly) poor accessibility of the cellular network after the blasts: "Gut instinct suggests that the network must've been overloaded with people trying to find loved ones. At first, the Associated Press said it was a concerted effort to prevent any remote detonators from being used, citing a law enforcement official. After some disputed that report, the AP reversed its report, citing officials from Verizon and Sprint who said they'd never had a request to shut down the network, and who blamed slowdowns on heavy load. (Motherboard's Derek Mead was able to send text messages to both his sister and her boyfriend, who were very near the finish line, shortly after the bombing, which suggests that networks were never totally shut down. Still, shutting down cell phone networks to prevent remote detonation wouldn't be without precedent: It is a common tactic in Pakistan, where bombings happen with regularity.)"
Why the network operators didn't get requests to shutdown the network, that doesn't mean it wasn't jammed. The military has jammers it uses where they suspect IEDs to prevent triggering via the cell network. There is no reason why the BPD, DHS or other agency would not have jammers for such an occasion. I would be surprised if they did not with all the money that was thrown around after 9/11
I would think that shutting down cell towers wouldn't be particularly effective, given that the same mechanism that would allow one to trigger a bomb with a cell phone is also present in other RF devices such as baby monitors and walkie-talkies.
while(1) attack(People.Sandy);
Could be any other means to detonate, but doesn't smack of precision. I have the feeling this is a loner, not a coordinated team who did this. So many unexploded packs found.
A feeling of having made the same mistake before: Deja Foobar
After the Earthquake in Virginia in 2011, you couldn't make a cell call to save your life, since several million people picked up their phones within a few minutes of each other. Text messages went through fine within a half a minute or so. Something similar happens whenever an unexpected event of note happens anywhere.
Boston slashdotter, here (as if that mattered). Anyway, wouldn't it be as effective to just disallow inbound calls/sms/etc? Allow people to make outgoing calls to call friends and family and all, but don't allow phones to receive calls.
All it would take is a text message instead of a phone call to detonate something.
Something's really weird going on with this whole mess. Given redundancies and failover capacity, I'm having a hard time believing that simple load caused failures that blocked cellular transmissions, especially as the failure occurred pretty much right after the blast, and not enough awareness would have been out there to cause the level of traffic needed to bring down the cell system soon enough to have had any effects in blocking cellular-detonated explosives.
I'm not a conspiracy nut, but this whole bombing bothers the hell out of me along with some of the other oddities involved.
Where are the statements from the NRA calling for the legalization of bombs in accordance with the 2nd Amendment? After all, bombs don't kill people, people kill people.
I almost never use text messaging, but it is extremely useful when cell networks are overloaded as it uses almost no bandwidth and hence messages almost always get through. Unfortunately not many people think of it that way and tend to keep trying to make a voice call when the network is rejecting their attempts.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
Talk about the telephone effect: local news never once said the cellphone network had been shut down. Instead, they repeatedly asked viewers not to use their cellphones to make calls or send texts, on the off-chance that such communications would set off any remaining bombs. By inference, that would mean the network was up and running.
I actually found it distressing that the media reports subtly added more drama the further it traveled from Boston. I was pleased that our local news was so even-keeled. The event was so shocking and saddening enough.
Voice and SMS texts go over different channels.
When I needed to reach friends after 7/7 (London) I used SMS by preference, because the voice channels were saturated with "Are you OK?" calls.
The only time I ever see SMS traffic slow down is New Years, when everyone tries to SMS everyone else at midnight. Although that's becoming rarer thanks to WhatsApp, Facebook, twitter..
that during an immediate crisis or disaster, cellular networks will become quickly overloaded. network providers acknowledge this and tout things like COW and COLT (Cellular on Wheels and Cellular on Light Truck) as a solution. what isnt clearly stated is that these systems may be hundreds of miles from the immediate area, or may rely on existing trunks and uplinks that are themselves completely saturated, if they havent been destroyed by $crisis || $disaster. cellular providers also have a terrible habit of booking these emergency systems for sporting events to augment their second rate cellular networks.
For geeks who understand how cellular works its limitations are pretty obvious, so im seriously wondering if amateur radio played any part in assisting during this crisis?
ham was designed from its inception to help in a civil emergency, and it would be hard to imagine an event like the boston marathon without at least one 2 meter or 6 meter general class or extra present.
does boston use ASTRO? or EDACS radio networks for emergency services? if so how did these networks perform?
Good people go to bed earlier.
Whether cell towers were working or not is a stupid thing to focus on, here. How about the coming absolute surrender of all remaining liberties? Since 9-11, I've repeatedly pointed out that all we need is one more big terrorist event to shake the population enough that we will give up everything. Complaits about the TSA, second amendment, privacy, government and corporate wiretapping without justification. All of it. It is over. We lose.by attacking us, we shell up. We take away our own freedomFOR them. It is time to shutter yro.slashdot, because it no longer matters.
So... considering that's we hear about this with EVERY major catastrophe, would this be the sort of national infrastructure concern that we would want to mandate that the cell companies install extra capacity? You know, in case of emergencies. Are we at the point that we can consider cellular connection, or generically wireless connection, to be a basic utility and not a cutting edge hip new ordeal that only the rich can afford?
And hey, since they've got ALL THAT BANDWIDTH, just lying about in case shit hits the fan, it'd be great to sell it on the cheap. You know, that idea that society and the fundamental utilities is here to foster growth rather than wringing out the last coin from the customer's pockets.
Uh.. doesn't this happen after just about every disaster?
If you design the networks to work at the utilization that you see after a disaster there would be cell phone towers at every corner, our bills would be $500 or more a month, and it would be using a very low percentage of its capacity 99.99% of the time.
It isn't what is important at the moment, anyway.
I believe SMS piggy-backs on a transmission from the tower which is a different protocol than what is used for voice/data*. It seems possible that SMS may work when voice/data has been blocked.
"transport messages on the signaling paths needed to control the telephone traffic during time periods when no signaling traffic existed. "
[*] - http://en.wikipedia.org/wiki/Short_Message_Service
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VZW appeared heavily overloaded and calls were not going through. Additionally, text messages also appeared to be throttled or heavily delayed. If this was a result of jamming or some other technology to throttle the network, calls were being placed, they were not however providing audio. I received about 20 calls from my girlfriend who lives in the area and her calls were ringing through and "completing", but no audio was making it over the line. Calls I was placing appeared to ring through (five or six rings?) and made it to voicemail in most cases, although I did get a couple Verizon messages instead of the voicemail box.
Text messages we were sending each other were either extremely delayed or never made it at all (some did). I would go with the disaster norm of badly overloaded. We resorted to email via wifi instead of relying on the cell networks. When she took to the car to pick up her sister in South Boston (T services were shutdown in and around Boston), she was able to start completing calls and texts were making it through.
Given the situation I think shutting down the cell networks would have been reasonable. They shut them down for G20 meetings and various protests but not in the middle of a bombing incident where there's a good chance cellular detonators are being used? Huh?
"When information is power, privacy is freedom" - Jah-Wren Ryel
Ah, the rush to misreport. This is why I wait a week to read about what happened. News outlets, and law enforcement officials, will just make stuff up because it's too early to know what really happened. Enjoy your speculation!
I think you wall off some capacity for emergency users (911, police, first responders) and do your best with the rest.
I agree, though there's some interesting ideas with having the phones themselves act as a mesh network to get information in/out of the affected area, but I'll point out that the military has been trying to institute something like that for decades with limited success. The idea is that a soldier's short range device hooks up with a nearby truck's, which relays it to another truck or plane that can relay it to the most appropriate ground station or satellite link. All dynamically.
There has been some progress on using relaying to extend the range of emergency radio networks - truck to truck to network, basically.
I don't read AC A human right
I don't know for sure on cell service, but there's a whole lot of other outdated information in that article. Specifically, the fire at the jfk library is now known to be unrelated, and law enforcement officials have stated that no undetonated devices were found.
* Media spouts a load of crap to get ratings
* News at 11
Oh wait, not news at 11, it's news all the time. Doesn't matter that there's nothing new to report, that it's all over, that it will takes days to get any more answer, we have to have wallpaper news because all the other stations are having it. Everyone's hoping for another 9/11.
Oh how I wish for a return to a half hour news bulletin 3 times a day, when journalists had time to go out and find what's going on rather than sit in a studio doing two-ways, reading wires and copy that's come from the studio.
That's enough from me standing outside an empty office block, back to you in the studio. I'll be here again in 15 minutes though for an update.
In such emergencies, its better to use SMS than place a voice call.
SMS rides on control signal and as long as your cell phone has a signal, it will get queued and delivered.
Voice calls require acquiring of a dedicated voice channel, these are limited and overloaded in such emergencies.
What if someone makes a cellular bomb that detonates if it loses its signal to the tower?
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Most cell towers have PRI lines that are dedicated for phone calls; it has a separate data connection for Internet and SMS transfers.
SMS, data, and voice all need to deal with the problem of timing - many signals sent to the tower's receivers at once can interfere with one another. Time division can only account for data; SMS and voice both send at random times (meaning the timing of the call or message send).
Having said that, some forms of TDMA have individual phones set up for only certain spots in the send time divisions; this can be overcome by many phones trying at the same time in the same division groups. CDMA has simple collision and overload of collisions per frequency, per coded divisor.
Having said THAT, there are generally (depending on location of course) only 24 (or 23) to 48 (or 46) voice channels allocated in the PRI form. Yes, most mobile phone companies are still using PRI and not channelizing through data connections as most think has happened. Only the busiest locations with many separate towers in the same area use channelized grouping through data connections (fiber or copper); again, most still simple use PRIs because they're CHEAPER.
If you get everyone using their phone at the same time it will fall apart. They don't build the networks to handle everyone calling and texting at the same time. I doubt they can handle half the customer base for the city at once.
But the opposite actually appears to be true, when the "emergency" is in an area where a lot of folks are trying to use their cell phones at the same time.
During some weather catastrophes a few years back, I could not get a single call to go through on the biggest carrier in my area, but texts did go through successfully. It's just less data packets to carry the information.
It's also interesting to note that the failures of cell networks illustrates the cell carriers overselling of their networks, or to say it a different way, their failure to invest in their infrastructure to adequately support the number of customers they have.
If you were to build a jammer, simplicity and reliability would be what you'd want. What that means is something that just floods the frequency range in question so that it is unusable. Simple and effective. That is, in fact, how jammers work.
To try and jam only higher level things like voice calls, while leaving alone SMS, would require a far more complex jamming solution. Something that would actually go and interact with the cell network in some way. It would take a lot more hardware, for a lot less reliable result.
So you are completely correct. There just really isn't a scenario where it would make sense to have a jammer that could only jam part of something where a jammer that jams all of something is in fact easier to make.
The thing that gets me is how incompetent the Boston PD were in policing the finish line. First, it's inexpensive nowadays to setup lots of cheap digital cameras for video capture of area. Second, how could they not have dogs about sniffing the crowd? Third, they didn't notice someone walking around with a freaking duffel bag!??
Can they even legally do this? Didn't San Francisco have a plan that included this and the FCC was like, "No you don't. We control broadcasting and we don't authorize use of jammers for any reason."
Similarly IIRC stasdiums and businesses can't, either.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
What is more likely? an explosive device, loaded with a cell phone that required a working/registered/traceable SIM, or a generic clockwork egg-timer or other mechanical clock, or if you are really high tech maybe a small micro like an Arduino, or just an RTC clock module, using the alarm signal?
After all, the device didn't have to explode the second that a motorcade drove past, just sometime in the next few hours would do fine
What I don't understand is why why would you time it when most of the field have been through? Surely for maximum impact you would want to have exploded it earlier?
Why the network operators didn't get requests to shutdown the network, that doesn't mean it wasn't jammed. The military has jammers it uses where they suspect IEDs to prevent triggering via the cell network.
Ignoring the obvious idiotic question of why would I expect the military to be standing around with jammers set up and ready at the marathon, what makes you think that this is even a good idea? Little background here..
It seems that in Iraq, the insurgents were using cell phones to remotely detonate IUDs. So the military deploys jammers. The insurgents counter with IUDs that detonate when they lose signal, indicating jamming is occurring.
SO, assuming that they had the capability to do so, what makes you think that jamming is the correct response? You may just set off another wave of explosions when you flip the switch.
HA! I just wasted some of your bandwidth with a frivolous sig!
This incident could have been substantially mitigated by .....
I'm going to stop you right there, because you are just playing 'armchair general' now. First off, if someone wants to be a terrorist, its going to happen. Moving the cans around would only change the way they attack. Second, hindsight is 20/20, so you can prattle on all you want about how this could have mitigated the attach, but its just speculation and hot air. Pearl Harbor wouldn't have happened if we put everybody on alert, JFK would be alive if he drove with the top down, Napoleon would have won at Waterloo if bleah bleah bleah. Just stop.
HA! I just wasted some of your bandwidth with a frivolous sig!
Officials also announced a twist in the probe: Suspicious packages that were detonated out of precaution were not explosive devices after all.
That's not a twist, it's just a thing. A twist is if it turns out to have been Richard Simmons.
No, a twist would have been if they suspected that it was Richard Simmons and it turned out to have been Gene Simmons.
HA! I just wasted some of your bandwidth with a frivolous sig!
Mobile phone networks typically use ALOHA, which fails utterly under heavy loads. It ain't a long queue, it's three stooges syndrome.