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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.'"
I realize that TFS is a copy & paste job, but WTF? Whomever was quoted shouldn't be allowed to use a phone ever just because they can't speak coherently.
Anytime you have a large population in a small area all wanting to make calls, the system will be overloaded. Capacity is built for normal use (which is probably 95 or 99% of normal call volume). When there are spikes in demand exceeding this volume, the network will not work as well (or even fail). Also if the network is physically damaged (such as Hurricane Sandy) it won't carry even normal call volumes. How is this not common sesne ?
They also said that Marcellus Wallace threw a man out of a window for giving Mia a foot massage.
Post a source, or STFU.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
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.
CB, and Ham for emergencies. Get it. Love it.
The CB is also a really good way to get real-time traffic updates.
well yes and no. You cannot break a radio transmission like you can with a phoneline or a cell system that gets overloaded. So 2-way radio is good for emergencies.
However, I have been changing my tune about ham radio that its real values are DIY/hacking/experimentation. You still have to pay a license fee (measly $14 to FCC every 10 years) and pay for equipment. You can open it because you own it (cannot do that with many cellphones) and you can modify it as you please (just keep the RF inside the ham bands). And when you have skill and talent to design/modify/implement wireless systems, you can be valuable to those who cannot.
Promoting ham radio only by emergency uses is limiting. Let's be honest, how many disasters occur that ham radio pays a key role? Not many (but don't get me wrong, many public safety officials see amateur radio operators as important resource). So all these people that get caught up in one-day ham cram and take ARES/RACES classes, then wait for the big one.... they get bored and go off and do something else. Emergency planning is important but it is not action-and-adventure where the hero ham parachutes in for the rescue.
CB can be great for traffic updates but for here in Silicon Valley the band is dead. There have been times when the highways backup beyond normal, would be great to call someone couple miles up 101 and ask what the situation is. But this is Silicon Valley and nobody comprehends frequencies less than 800 MHz.
mfwright@batnet.com
Very much beside the point. Only a relatively small percentage of connected landlines can call out of area at the same time. If there is a reason for many people in an area to call or be called at the same time, POTS users experience congestion just like mobile phone users do.
The POTS (plain old telephone system, for the young whippersnappers) didn't have unlimited capacity to connect calls either. When many calls were in progress in an area, you could pick up the phone and hear the congestion tone right away.
That's in the days of computer phone switches. In the old days of mechanical relays, there were a fixed, limited number of dialtone generators (and first selectors -- the stepper that handled the first digit you dialed), so if local capacity was reached you just didn't get a dialtone right away.
You still hear this today, but usually after you dial. It's the fast busy signal. The fast busy means circuits are busy, try again. The slow busy means the destination line is busy. If you try a fast busy again right away, chances are good you'll get through, and you'll confuse the person who answers if you accuse them of being on the line when you called a minute ago.
Mother's Day was a big holiday for calling, so it was more likely to hear, or not hear, this happening then.