How 9-1-1 Technology Works

and welcome to tech Stuff. My name is Chris Polette. I'm an editor here at how stuff works dot com, and sitting next to me, as usual, is the very helpful senior writer Jonathan Strickland. You know what I think you need help? Do I? Yes, when I need help? Do you? Because you're in the United States that it occurred to me after we researched this that it is once again a very United States centric podcast, So we apologize to our friends overseas and to the north and South.

And okay, okay, well, let's let's just say, how does a rescue number fill in the blank? Here? You know where you are. Well, you're making some pretty big assumptions there, Pete, because I haven't looked into any others other than one. Okay, well, I think the technology is basically there, so let's talk about the same. Alright, So let's first talk about how nine one one is set up. We were gonna really focus kind of on on how it works when you're

using a cellular phone or heaven help you avoid phone. Um. But but before we get into that, it's best to know kind of the basics of how it works in the first place. Sure, I mean, it wasn't all that long ago that there wasn't any kind of standardized number, you know. You know, it's only been since the mid nineteen sixties that for the sixties eight was when the first one went live, right, Well, I mean they had to, you know, work on getting it organized and it wasn't

even a national thing. It is very localized and it's still listen, it's it's it is. It is very much a regional system. So um, yeah, there's no national system. It's all uh managed by by different counties and cities. Yeah yeah, different uh, different governments and and different regions are overseeing these things. So as you can imagine, coordination

is a is kind of a tricky, tricky business. One and um, usually you know you're you're pretty much supporting it through taxes and uh maybe a fee to your phone carrier. Yeah, yeah, I mean it's uh. In addition to building out the network, they have to pay people to sit at the switchboard and listen to people with emergency calls and those people who call to complain about traffic and that there are no chicken nuggets at the McDonald's.

You totally stole it before I could say it. Yes, I win, okay, so um, yes, uh, let's let's say let's start with the landline um approach, because that that's the easiest one to talk about when you're when you're making a call, and it is the first one they had to, uh to worry about building out. Right, so when you actually dial, it goes to a different hub.

It doesn't actually go to the same hub that regular phone call will go, right, because the phone company knows when you make a phone call, it has to that's right, that's right for them to bill you exactly exactly. So when you make a nine one one call, the phone company knows you're making an emergency call. It goes through this hub and then it goes to the closest public Safety Answering Point or P s a P SAP SAP, so it goes to the closest one to whatever region

you're calling from. So that way the response is going to be very localized and theoretically will be the fastest response that you could expect under you know, any normal circumstances. Now, UM, when you call the the phone company sends to that SAP P s a P. That the your information, so that person will know the operator will know like this

is where the phone calls originating. UM, in case you aren't able to speak, If you are unable to actually talk, UH, they can at least see where the calls coming from and send help to that address. And this happens, you know, more often than you would think. You may not be able to speak because you smoke inhalation, you might be choking on something. In some cases, people's pets have dialed

dialed one, and in some cases it was necessary. I mean more than one case you had an animal dial nine one one and it really didn't need to do that. But but there are stories about rescue animals that did dial nine one in order to contact UH emergency services when their their owners. UM suffered some sort of trauma and uh, you know, of course that doesn't happen all that often. But the way the system works is the operator sees, okay, this call is coming from this address,

I will send help there. I can't quite ascertain exactly what's going on, and so they, you know, pretty much decide at the spur of the moment which services to send. UM. Otherwise, of course the dispatcher will talk to the you know, the operator or dispatch will talk to you, and then you would explain what the emergency situation was, and then they would send the appropriate respond respondents. Right. So UM,

that's the that's just the basic uh response. There's actually another thing called the enhanced nine one one response, which is even a little more complex than that. Yeah, E nine one one is UM actually fairly common now, I would think, yeah, yeah, back in two thousand and six, I think it was penetration in the market, So by now I would expect that number to be much higher. So UM, and it actually uses an even more sophisticated system.

The hub that you dial into UM actually makes some additional determinations, goes in and get some info from a couple of servers on the telephone system side to try to get even more detailed information about where you are and and who to route the call to to maybe

speed up the service just that much more. Right, Yeah, you're talking about things like, you know, to everything from determining how many emergency calls are already out to you know, maybe maybe this person's address would make you think that they are closest to this P s a P, but in reality they'd be closer to another one. Um. It also will bring up information such as what what sort of obstacles a response team might encounter en route to the address, like if there's a street that's closed or

anything along those lines. Um. So it really is of course designed to help these emergency responders get to you much more quickly and safely than they would otherwise. And as it turns out, this enhanced nine one one functionality is essential to getting wireless nine one functionality to to actually function the right way, because otherwise it would be very difficult for the the wireless provider to get the

information on where you are now. You know, a cell phone can only be so accurate as to where they can figure out where your location is because it's triangulating based on the signals from different cell phone towers in your area. Uh. So it's a little like GPS in that way, because it is is determining your location based on the transmitters on the ground and where the phone is telling it that it is. You know, it seems closer to this one, it seems rather away from that one.

We think he or she is in this area right here. And UM, this is important because around of all phone calls that go into originate from a wireless phone like a cell phone. And UM, obviously when you have that that number of calls coming in, you do need a way that you can, you know, retained where this person is. Um. There are a couple of different ways of doing this

besides the one you mentioned is probably the most common. Uh. That one is the uh it's a network based location finding is kind of the way we think of it. It's in the sense that it's all based upon how far away you are from at least usually I think three towers that's what they need in order to to determine where in general you are. I think that's the

number that I saw most frequently. And yeah, it's it's accurate to between one dred three, which is you know, not that bad considering, but there's if you're you know, in your car and it's on fire with flame shooting out through the hood, I think they'd probably be able to find you once they got once they got within three they probably be able to figure out what they know.

But the other way you can do this is actually using a handheld device like your Your phone itself has within it a location device that would help in that. If you have a phone that has a GPS receiver, it could it could send the information it's receiving from the satellite on through the signal and therefore give extremely

accurate location information to whomever's on the phone. Right, So it's getting the the information from the GPS and sending it over the cell phone network, right, That's exactly what it's doing. However, you have to keep in mind if you're inside, that's not going to help you out too much. You really need to have an open view to the sky in order to to really get those signals from the satellites. Uh, if you are in any kind of like heavily wooded area or maybe downtown in a really

crowded city, um, it may not respond as well. So that's not always necessarily, Like, just because you have a GPS receiver in your phone doesn't necessarily mean it's going to give it the most accurate information all the time. It all depends on the situation you're in and the

environment around you. That's true, because I'm guessing that if you were saying in a the story building and you have a GPS device and it's saying, well, you know he's here at this location, then the rescuers have to go look on every floor because it doesn't say, well, you know he's on the fifth floor and sweet five forty, so well yeah, yeah, so even if it could get the signal in the first place, so there, so there

is a limit, Yeah, there are there are limits. And the whole reason for this in the first place is because the the FCC was very much concerned with making sure that when you dial nine one one on a cell phone that you are able to get the help that you require, and uh, they demanded demanded things to be rolled out the sort of the enhanced nine one one for cell phones to be rolled out into two phases.

The first phase was just using location determining your location will be determined based upon whichever cell tower you are connecting to with your phone, and unfortunately that doesn't really give you a whole lot of accuracy. We're talking like six to thirty miles, and six to thirty miles is not great. Now, hopefully, if you are actually able to communicate with the operator, that won't be as big a deal because you'll be able to tell that person where

you are right right under Phase two. It's it's much more accurate within fifty according to the government information. And uh, I was actually looking into this now. Here's the other issue is that you might wonder, like, okay, well, how far into phase two are we? That is practically impossible to answer without contacting each and every P s A P in the nation because it's on a per carrier basis. It's on a per P S a P basis. They have to work together in order to get this Phase

two rolled out. So um yeah, it's I couldn't even tell you, like, how how many different locations have Phase two rolled out versus Phase one? Um, it's uh and that's kind of scary when you think about it. I mean, you know, you really don't know when you call nine one one if how accurate their their information is going to be um. Of course if you can talk, then that might be able to solve some issues right there.

But yeah, you know, uh, just to point this out, UM, from what I was reading during my research fees on this podcast, Uh, the experts say the very first thing you should do when you call nine one one is to tell them where you are. Um. Especially yeah, exactly because they said that that that is probably the most important thing, especially if you're in a situation where you're not able to communicate well, because um, you know, then they can go ahead and figure out how to get

to you and from there, you know, assist you. But yeah, that's you know, don't forget to just go ahead and tell them where you are, um, because that is is essential when you're dealing with wireless and v O I P. I didn't think to at this in my notes, But we should also addressed the fact that if you carry a satellite phone, that can give information very quickly to an emergency response team exactly where you are. Because again that's working on the same sort of of uh kind

of way as a GPS receiver. You're receiving yourself signals through satellite UM, and there are many satellite emergency phones that are on the market for people who like, you know, like to hike in the Yukon. Sure's things like that. You know, people who really do go into these you know, high risk environments because they're they're adventurers at heart, and uh, these sort of phones help help get that information out.

And usually it's a simple button you press and it sends an emergency signal and it includes your coordinates like on Star in cars. Yeah, essentially, yeah, it's on Star for hikers. Yeah. And very expensive. Yes, yes, they are not cheap. Yeah, we're not talking like your voice plan. I think they're significantly right. Both the phones and the

plans cost quite an out of money. But if it's a matter of life and death because you're an adventurer and like like to go out and you know, party with grizzly bears who might eat you and who doesn't write, you know, I might be worth the investment. So let's move on to voipe over Internet protocol. That's true. Now, voice over Internet protocol we've talked about before in this podcast.

This is uh, yeah, this is uh, this is It sends your phone call like it would send it sends it over the internet esppecially over the cellular network, and uh, like every other kind of information that's sent over the internet's broken up into packets, gets little pieces, teeny tiny pieces like you know, like a Mike TV and Willy Wonka flies through the air, and it gets to the other side and gets re it gets put back together, and then it becomes the phone call on the other end. Uh.

Here's the problem with voipe. Um, there's no physical location associated with voipe at all at all. You your voice is associated mainly with your computer or device upon which you have voipe installed. That's true, I mean there is you know, you can ping something a location and get as sort of an idea of where it's going to

because you know, and internet. Anything you send through the Internet reaches lots of computers, tons and tons and tons of computers because it's it's bouncing piece by piece over you know, network by network, different stuff in between here and there. The thing is, you know, there's very it's this information that's coming around with it is very sketchy. So it's you know, it's general idea of where someone is.

But the other thing is that, um, you know, it's it's you can set a location when you set up a voipe account. In fact, you're supposed to UM, which would be you know, like the idea here is that you're telling the company this is where I usually I am usually at when I make my voice calls, like if I I'm usually at home when I do this VOPE system. So that way, if I were to ever call nine one one over the VOPE system, chances are

this is the location that I'm calling from. UM. And then theoretically you should have an easy way to update that information so that if you were to travel, you could say I happen to be in Prague. Not of course, if you're in Prague, I don't know why you'd be dialing one, but the point being that you should be able to update your location so that UM, you're not sending the operators on a married chase or really it's just to let the phone company know which P s

a P you're calling needs to be rounded to. Yeah, it's not gonna do much good if you call nine one one and the person answering the phone is eight counties away and uh, you know, it's just as all that's gonna do is waste valuable seconds. And of course we know like in an emergency, every second counts. Yeah, if you're if you're a v O I P telephone customer, for example, if you Advantage or many of the others. A lot of the regular I s P s and phone companies offer some kind of v O I P

service Now UM. They'll tell you whether or not you can use UM, and they sort of have some of the details ironed out. However, if you were to be using some of the UM programs like Skype or Gizmo Project, I don't know that it would be as reliable as you know, something like Vantage, which is you know, set up to be. It's like, well, we know where he lives, he's calling from this address. It's fine. Now, the FCC says that any VOIPE provider has to provide support and

it has to work. Uh. They don't go so far as to explain how that's supposed to happen, but they say this is how it has to be, so it's left up to the providers to find a way to make it work. Yeah, that's the thing. I mean, if you're if they know that you have a voice power line system at your house and you're calling from your house, well they know where that is. They can it works. It would work very similarly to a regular telephone call. I would assume in that UM they would say, well,

h Chris is calling. We know Chris lives at this address, send him here and that would be it. But you know,

it's not because of the voide. It's because they know they already know where you live, right And according to the f c C, interconnected voite providers must obtain affirmative acknowledgement from all existing customers that they are aware of and understand the limitations of their nine one one service, and they do send that information to you if you're a customer, because I am a v O I P customer, so you actually received that excellent, So good on them.

They're following the law. UM. But yeah, it is important to remember that if you're a void customer that that could become uh an issue. However, we should also point out that, UM, you can also make nine one one calls from any cellular phone or really any landline. I think I think you can make an emergency call all no matter what, you don't even even if you don't have a plan anymore on a cell phone. If you pick up a cell phone in don nine one one, it has to work, right, that's true. I mean that's

if you have an old cell phone. Um. I've actually heard this mention before by a consumer. Um consumer rights advocates said, if you have an old cell phone, you know, traded in for a new one, go ahead and keep it charged up, the old one and throw in your glove compartment, because what if you leave your cell phone at home, you get an accident, you still are supposed to be able to call nine one one, and they're still supposed to connect those emergency calls. So it's a

good use for an old, beat up phone. Yeah. I know, there's some charity organizations that accept donations of old phones specifically to use them as emergency phones for underserf populations.

So um, so yeah, that's that's a good thing to keep in mind is even if you do use voide, it may it may behoove you to keep a regular old phone plugged in or a a cell phone laying around so that you can rely on that in the case of an emergency, just in case the voide doesn't work exactly the way you would hope it would work, and in which case you would want to tell them where you are first. Yes, always remember that I'm done. I am too excellent, because you know what that means. Yeah,

it's time for listener mail. Yay. I'm trying a new approach this time. Yea, yeah, excellent, all right. This listener mail comes from Andrew. Hi Andrew, He says hello, Hey, look, he said hi back. My name is Andrew from Illinois. So he's the Andrew from Illinois. Hi, Andrew and Illinois. He's in seventh grade and I'm subscribed to what is it now? Seven? Yeah? All seven How Stuff Works podcasts. You are awesome, Andrew. I just thought i'd dropped you

a line. Aligned to you guys at tech stuff and say the specifics about the five major web browsers Internet Explorer, I have eight Mozilla, Firefox, Apple, Safari, Google, Chrome, and Opera. I have all five on my laptop, and although Internet Explorers the easiest to use, best for favorites and bookmarks and a few other things, there's in no way the best. Firefox is by far the best and safest of them all.

Safari is the fastest, Chrome is stripped down, making it an easier interface to use, and Opera makes the best backup browser and is great on older computers. I know that you probably know all this already, but I just wanted to say what I believe about them. I never owned and hardly ever used a Mac before, by the way, I just wanted to say that I am slash was bared and it is PM by five pm and seventh grade. Yeah that's okay, Yeah, I'm I'd say bedtime at ten. Yeah,

we'll ask my bedtime now too. Good Lord, well, Andrew, thank you very much for writing it. Um five browsers on one laptop. Oh, we'll see. That's that's because that's you see, he's not using a Mac. Because if he was using a Mac, you have those plus OmniWeb and Camino at least if not, Shira, I'm almost sad that I picked this mail to read. You know, you're right though, because each browser they're all they're all good. Uh, and it's it seems like from using all of them, there's

always one thing about each one of them that goes. Man. I wish everybody else would do this, but they don't. Yeah. Yeah, I can think right off the help of my head. For instance, UM, i'd say the Internet Explorer probably has the most widespread support any website to work in Internet Explorer. Um, it's also out of the major ones, it's the slowest. Although Internet Explorer eight is faster than seven. I think, what was it, Safari was like thirty six times faster

than Internet Explore seven. Yeah, it's only like eight times faster than Internet Explorer eight, so it's it's improved. But yeah, um, actually I think and and Andrew sent this for a while ago. I think I should point out that Google Chrome doesn't have a new beta out that's even faster

and bite me, Safari. Disagree with you, Andrew. But they had a contest not too long ago which they let crackers, won't their white hat hackers take a shot at the different Uh stop laughing at me the joke alright, go ahead anyway, they let some some hackers take a shot at the security on the different browsers, and the one that withstood the attack the longest was not Firefox. It was Chrome. Yeah. Chrome, actually did did they ever break it? I didn't see a final I think they finally just

gave up at the end of the first day. That was the only one that they hadn't actually managed to crack. Um, however, you don't have all the extensions and flexibility of fires true? Is that true? I I rely on Firefox primarily, and then I use Chrome is my backup browser, and then I use Internet Explorer for whenever I have to access anything. Uh internally, I still have a soft spot in my heart for opera, do you yeah? And Safari is pretty you know, there's some good things about all of them.

I'm more of a musical fan than an opera fan, and I'm just gonna stop with that. Okay, So I guess that wratches things up. If you have any questions, comments, or suggestions, you can write us at tech stuff at how stuff works dot com. And remember we have blogs up. You can find those at how stuff works dot com, as well as articles about all the subjects we've been talking about so far. And we hope to taught you again really soon for more on this and thousands of

other topics. Is it how stuff works dot Com brought to you by the reinvented two thousand twelve camera. It's ready, are you