[VLM]

"Apparently cellphone service is SHUT DOWN! To make sure new devices are not remotely detonated!"

Oh no. This has been done a lot of times recently and all it means is future devices are going to be designed to go off when service is lost. Like every time you get a text message the 10 minute "reset" button is shorted. On the bright side AT&T outages are now a feature not a bug as they make constructing and transporting devices like this very exciting for the bad guys.

[jlgreco]

That seems like an overly complicated way of doing something that could just be done with a timer. (I don't mean to provide tips of any sort, but that seems kind of obvious to me.)

[gavinlynch]

You are correct. This is a very common scenario. The trigger is the cell phone's vibration motor, which is removed so the IED can be connected to the phone. A timer is set, the signal to the motor is sent and activates the trigger, entirely without the use of radio waves and obviously without needing a cell tower.

[VLM]

I'd disagree in that:

1) No signal = the primaries have gone off and the area is swarming with panic evacuees and rescue personnel and full of news cameras = almost the definition of the perfect time for the secondaries to go off.

2) If the purpose of the attack is terror, what better way than shutting off communications then creating an intense demand for communications? And you get to make the authorities feel guilty about it?

3) This also fits in with jammer mentality. So if a jammer protects against IEDs, the obvious counter response is a weapon against jammers. So next year's run, if there is one, will have a motorcycle pace vehicle with a very highly publicized jammer mounted on it for the purpose of security theater, the pace cycle/jammer rides past the trivial to imagine and design jammer detector, and ...

It all boils down to I can't figure out a realistic alternative way for the good guys to help the bad guys more effectively than shutting down the cell network.

[gcb0]

1. most devices are simply cell phones with the trigger hooked up to the vibrating motor wires on a cellphone

2. i don't think even suicide bombers are crazy enough to trust any american cellphone operator coverage claims.

[rdl]

Yeah, due to localized jamming in Iraq (for convoys, using Warlock and better), there were "increasingly sophisticated" systems.

The correct way to make the best IED trigger would be something which required an ongoing cryptographic challenge with nonce or time, so you were safe from both having your circuit cut AND from people finding/replaying your signal.