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Why It's So Hard To Make a Phone Call In Emergency Situations
antdude writes "BoingBoing reports on why it's 'so hard to make a phone call in emergency situations.' Quoting: '[The thing about] the radios is that they have different sizes of cells. You've got regular cells and then smaller sub-cells. You also have larger overlay macro-cells that are really big. They try to handle you within the small cell you're closest to. But it's a trade off between capacity — they'd like to have lots of small cells for that — and coverage — they don't want to put 100k small cells everywhere. So you might have a cell that covers a mile ara and then smaller cells within that that handle most of the traffic. ... In the end, it does come down to trade-offs. That's true of any network. You're interested in coverage first and then capacity. If you wanted to guarantee that a network never had an outage your capital investment would have to go up orders of magnitude beyond anything that is rational. So each network is trying to invest their budget in ways that make network appear to perform better. The cost of providing temporary extra capacity for the Boston Marathon, that's something that's in the budget and they plan for that event. But when you get something unexpected like a terrorist event, or an earthquake, or damage from a hurricane or tornado, then you have trade offs between capital and how robust your network is. Every time you have an event people say, "Oh, they didn't invest enough." But you look at New York City after Hurricane Sandy and Southern Manhattan was under 6 feet of water — all the buried infrastructure was lost.'"
Yep, pretty much have cell phone congestion during any large crowd event, such as parades and concerts and demonstrations.
All it would really take is some sort of public education campaign to use SMS in those situations.
911 does take SMS nowadays, does it not? If not, I hear SMS to Twitter / Facebook has been useful for getting people to reach out to their friends for help, who can in turn call an emergency response number... somewhere.
Part of it's not just whether the network fails, but how it fails. For instance, in a situation like this the network might be reconfigured to reject incoming calls to the area to keep that capacity free for people calling out. It might start throttling back voice calls to free up that capacity for emergency services and keep the data portion of the network running (and maybe drop the data portion back to 3G or even 2G so it could handle more simultaneous users). You wouldn't be able to call out, but you could still send and receive text messages. And the process for this should be in place. This kind of thing is rare and you can't predict when it'll happen, but it's a given that it will happen so the network operators should have a plan in place for what to do when it does.
And they should also be looking back to Ma Bell's studies on how to staff operators to handle phone calls. They found through a lot of study of real-world traffic that you can't staff for the average volume and successfully handle the calls. Calls tended to cluster, so if you wanted to keep wait times acceptable you had to staff for the peak volumes and accept that that meant you'd have idle capacity a lot of the time. I often get the feeling that the engineering side of the carriers understands this, but the business side doesn't quite grasp the idea of call volume not being a normal distribution.
gets shit thrown at it from both sides. providers dont feel the need to invest in more towers and users understandably get angry when this problem manifests in dropped calls and network outages.
to curtail the issue, emergency coverage services like COW and COLT (Cellular on Wheels, Cellular on Light Truck) have been bastardized by carriers to augment connectivity for sports events and serve as standby relays during repairs. COW and COLT were designed by the industries to respond to hurricanes and tornados but the allure of having a tower-on-wheels it understandably too budget-friendly for any carrier to pass up. oversubscription and markup are what keep cellular industries alive, just like shared hosting or airlines.
the other issue is as TFA highlights, cellular is just not as robust as say, 25 core ASTRO multi-zone digital radio...arguably because the need just isnt there. if 1 in 5 people cant make contact during an emergency its not a problem, cellphones can be borrowed or the calls can be retried. in law enforcement and emergency services, the PTT button has to work every time no matter what, as a loss of service could result in an emergency turning into a catastrophe.
finally, what i consider 'dark devices' can also create an outage automatically. fire alarms, burglary alarms, and even SIGALERT and some EAS systems (yes, EAS, its cost saving/kickback jack-assery found in flyover states all the time.) for the city/state are critically dependent on cellular networks. in the event of an emergency the activation of hundreds of these devices at once can black out the network pretty fast.
Good people go to bed earlier.
For those who are having trouble looking it up, Cocoanut Grove fire on Wikipedia.