Today, the US govt must explain why its rules on shutting down whole cell networks are a secret

WTF..

I would think that the rules would or should be public knowledge. If for no other reason than if there's a situation where the phones go dead, the average person might have a clue. Secret, secrets, and more secrets.... for something supposedly to used for our protection and could affect millions if the system needed shutting down.

"Even though it's highly likely the murderers used other means to trigger their explosions simultaneously"

Given there is (or was at the time) no mobile coverage on London Underground trains, that's an understatement.

Synchronised watches have been around since pocket/wrist watches were practical. Shall we ban portable timepieces too?

Telco experience.

Shutting down the network is unnecessary. The call spike during an "event" will see to that anyway.

GSM/UMTS etc systems have prioritisation modes. Under heavy conditions, registered priority devices will get through first time, every time.

There _are_ modes where only priority devices can make calls (this is different to shutting down a cell) but this is pretty much a nuclear option as it leads to every handset in the vicinity being frantically redialled and spins up the load on the cell.

Whether DHS can order a shutdown, and whether the conditions under which it might decide to do that are public, it remains unclear whether there is any requirement other than a cell service's commercial interest and agreements to support even having underground cell repeaters, let alone operating them at any particular times; or whether BART, as a regional quasi-independent government agency, might not have its own rules different from those of the DHS.

Aside from that, of course, it is rare for law enforcement agency incident response plans to be public information, and while I always thought creation of DHS to be ill-conceived and unwarranted, they would not differ in this respect from the BART or San Francisco police, or the California Highway Patrol. And I think we should expect that in future, and irrespective of the announced policy of any law enforcement agency, a riot could well occasion similar service interruptions. Officials may think it preferable to ask forgiveness after the fact than permission before. A lot would depend on the circumstances and judgment of those accountable for maintaining order and public safety, as perhaps it ought.

Da, Comrade. Together with our friends in Berlin, we will convince the proletariat these rules are necessary for their own safety. Then we will crush their means to communicate and travel freely.

I don't know why the DHS is resisting making this public: after all, if you have nothing to hide you have nothing to fear. Right?

Wrong European Capital

Cellphones were used fore remote detonation in Madrid, not London. Madrid also used real explosives instead of homemade peroxide devil's brew.

In any case - Madrid bombing is to some extent in a league of its own as it was not the usual suicide moron affair. If the investigation by Bulgarian TV at the time was correct, the technical part was not the handiwork of the 4 people that later blew themselves up at Leganes. According to that investigation, the design and implementation was done by a Bulgarian engineering dropout from Satovcha who has had at least some interactions with the Saudis while being trained as a radical imam after dropping out from the engineering school. So it actually has much more in common with 9/11 than London.

In any case, the cellular network will go down anyway (as London has proved) due to extreme congestion. It is not designed to handle the volume of call attempts resulting from 90% of the users trying to call someone to figure out if they are OK. No point shutting it down.

There is a tiny dot of sense in this..

.. although that would just lead to a restricted release, not a complete refusal.

The issue I can see is that by knowing the conditions that trigger a shutdown, someone could engineer a Denial of Service prior to a real atrocity (another commentard correctly suggested such could be driven by an old-fashioned time piece). Don't forget, the real aim of real terrorists (which do exist) is panic, and isolating people can contribute considerably to this.

That does not excuse not releasing anything at all, but I would understand that some aspects of it would remain classified. I also think that shutting down altogether is not a good idea - I like the UK approach to restricting traffic to permitted numbers better.

Adaptive thinking vs government

Terrorism makes use of adaptive thinking, something governments aren't known for. You can ban anything you like but a little creative thinking will render the ban useless.

For example; heartbeat on the cell network (sms every 30sec) and detonation once it times out. Kill the network, trigger the bombs.

More likely it is to protect government agencies from the dangers of a protesting public.

Explaining how and why...

...is not in the best interest of public safety. Certainly ever person can live without the use of their cellphone in a tunnel, regardless of where the tunnel is. It may come as a shock to some people but cellphone use in all areas is not some God given right, it's a convenience.

Temporarily shutting down a network is also not unreasonable in this day and age of terrorism. Get use to it because the bad guys are growing exponentially and you're paying for their growth.