How Bluetooth Works

it seems, uh. And it's one of several wireless technologies. It's if you think of wireless technologies on on a on a scale basis, Bluetooth is the really close in scale we're talking like, then you have WiFi, which extends can extend a little further than that, and then you would have y max, which could broadcast much further. So Bluetooth is a sort of your personal little small bubble of wireless allows you to connect different devices wirelessly to

other Yeah. For example, UM, to send ringtones to my cell phone, I might turn on my Bluetooth on my laptop and turn it onto my cell phone and then send the files over there. You can exchange photos or uh send you know, MP three's for your ringtones. It's also what you see when you see those little earpieces that people wear in public. They're wireless earpieces. It's the piece that connects to your phone, uh and the W remote actually uses it to uh communicate with the uh

the WE game system. So it's it's something you've probably seen, although you may not know exactly what it was at the time. Right, So if you were wondering what it what what those things were that we're making people look like cyborgs, uh, that would be the the Bluetooth headsets. Um. And also it counts for a lot of people apparently muttering to themselves in public when they're actually talking on

the fountain, right. Yes, it has certainly made me think that there were a lot more crazy people on the streets than I originally thought, and I live in a pretty crazy part of town. But turns out that a lot of them were just having conversations with their buddy, you know, who is a couple of miles away, legitimately, not in an imaginary way. So that's that's sort of

a relief. Yeah. Unfortunately, with Bluetooth, there are some security issues, just like there are with other wireless kinds of technology, they're just not their holes in there that that can be exploited readily by hackers. Right. The kind of acts like a sort of a walkie talkie in a way. You're you're you're sending signals by radio waves and uh and if you if you don't have your settings just right,

you're essentially sending them into the general area. Anyone could could intercept them or or start slipping little messages to you with you being unaware of where they're coming from, who they're from. You know. That's what that's what That brings us to the first topic of bluetooth security. Bluejacking. This is this is a sort of more annoying than dangerous most of the time. Yeah, Actually, as I was

editing this article, I was thinking about doing that myself. Basically, what you do is, if you have a cell phone that's Bluetooth enabled, you can add a message in your address book like you would add a friend, but instead of adding your friend's name, like if I were adding Jonathan to my address book, instead I would add a message called you know, how's it going. And then what you do is you turn on your Bluetooth and you look it tells you who is around you or the

devices that are Bluetooth enabled around you. And if you could find a phone in there, a lot of them look like a string of letters or numbers. May if you could find, say, Sony ericson T six ten listed in there, you could send how's it going as a

contact to that to that phone. And when somebody when you look around and you see someone's phone ring and they get this puzzled look, this person gets a puzzled look on your face, you know that you've actually blue jacked that person with this secret message, right, And and of course you could go a little bit, you could

have a little more fun with it. Uh. Many of the blue jacking sites talk about things like going to a mall and just kind of looking around to see who has a phone or an earpiece and uh and making some educated guesses about what device that person might be carrying. Because you don't necessarily know that the devices you see listed when when your Bluetooth device to text them, you don't necessarily know which ones belonged to which people.

It takes a little bit of guesswork. But let's say you see, uh, someone wearing a Ramones T shirt and you might want to write a little message saying I hate punk rock and you send it to that person's device and they suddenly get a message that has no identification on it saying I hate punk rock. They know someone's looking at them, they don't know who. Kind of freaks them out a little bit. Yeah. That, Um, that's

the security issue obviously. Uh, this isn't that serious. You're just getting secret messages and you don't really know who your admirer or detractor is. Um, but if you want to uh avoid being the person wearing a Ramon shirt and being I identifiable any wait wait, I just want to make one thing clear. Do not be the person who avoids wearing the remote shirts. Ramons are awesome. Where

Ramon's shirts they're great. Well, there you go. But if you don't want to be identified, what you need to do is, if you have a Bluetooth enabled phone, just make sure that you don't you know, if you if you use the Bluetooth feature, make sure that you don't identify yourself in this. You know, don't say this is Chris's phone in there, because then they're going to know that that's somebody's phone in that. You know, it's available

and ready to have a message sentulate. Right. Let's let's move on to some of the more potentially sinister bluetooth security problems, one of which would be intercepting messages, but another is tracking people and this is actually going on in a couple of different places. Um I was reading

a news story about bath in England. It was in the newspaper The Guardian, where the city was using this uh this program to kind of track people's movements, not in a way that could identify the individuals within the program, but just to kind of see where people were going,

what places were most popular. But it raises some some privacy concerns, and uh I remember in the article on our site we specifically talk about shopping malls using this to kind of look and see which places in the mall are the most popular, right right, Well, they basically do the same thing. You have an identifiable number or name in your phone and you carry it with you, then the bluetooth devices would basically have non identifiable information.

It's it's actually very much like a cookie on a website, because they would say, okay, well, uh j Q for ten is going from uh the Apple store down to the food court, and they would be able to know how much time that that number, you know, spent in that particular store and then went down to the food court, and they spent another hour down there, and then they went down to uh to the department store on the other end, it's spent another hour and there they would

know that much about you, but they wouldn't know your name and an address or phone number or any of that information, because it's not the same. But it is a little weird to think that people could be watching you as you go from place to place right there. And there's some people who still still assert that it's at least possible that eventually you could be identified by this information. It would not be easy, and there's not really much incentive for anyone to actually go through that

trouble to do it. But the fact that there may be some potential for that has a lot of people worried. I mean, you're talking about a privacy thing. I'm sure are are. Coworker Josh Clark would be upset if the shopping mall had identified that he had gone in and out of Victoria's Secret fourteen times. That's probably true and completely believable. Yeah, I'm not getting into that, um, normal, I get into why so many people in England used the phone in their bath. No. Yeah, alright, very cute,

but seriously, it's not like this identify. This information is really personally identifying, and they would have to go to a lot of trouble because, as you pointed out earlier, UM, Bluetooth is a very short range mode of communication, so they would have to have whoever is tracking you would have to have sensors, a lot of sensors, like every

twenty exactly, in order to to effectively track you. So we're talking about a system that is not effective as far as tracking individuals, and you know, for anything like an intelligence agency that's concerned with terrorism, for example, you would have to blanket entire city areas with tons and tons and tons of sensors and uh and it's just not practical. It would it's too expensive, The infrastructure would

be uh, pretty complex. So on a scale of one to tend, Bluetooth security is probably on the you know, three to four range. Just for your own personal information. Now, it is possible for people to use bluetooth to to hijack your phone. It is possible for people to get access to your information. Um. Again, it's not an easy thing to do, but it's it's possible. So you definitely want to be careful about when you're using those Bluetooth

capabilities with your devices. Um, if you're going to be in an area that, uh, that has a lot of hackers in it. For example, let's say you're going to a hacker convention, might not be the best time to enable all your Bluetooth devices. That's true. UM. Honestly, the easiest way to avoid any of this is to turn your phone or other Bluetooth enabled device to uh. You know, it'll say whether you're discoverable or not, that sort of Bluetooth jargon. And if you just turn it off, you

make it non discoverable. Then it's uh, it's impossible. Your the power is down, um and no one will be able to do that. And it saves battery life, you know, because if it's got that radio signal going the whole time, you know, it's it's draining your battery. So there there's another advantage to it right there. Well that's pretty much the inside skinny I guess on the whole Bluetooth security issue. Wouldn't you say I'd say so. UM, if you'd like to read more about it, we've got a couple of

articles for you. We have what is blue Jacking, which is the article about blue jacking and sending secret messages to people, and then how Bluetooth Surveillance works if you're more interested about the cobrat clandestine world of bluetooth security and um those are available right now on how stuff Works. Thanks for listening. For more on this and thousands of other topics. Does it how stuff works dot com Let us know what you think. Send an email to podcast

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