How Proxy Servers Work

have a proxy. Wouldn't you say? Yeah, I'd say so. You had another wonderful segue. Thank you, Mr Pilette. So this is in response to an email we received U. Tim West wrote to us and said, I'm writing to you on behalf of your podcast on parental controls. While I was listening to this podcast, I noticed you were talking about how your children would find ways to bypass parental controls. This made me think of proxy avoidance systems.

I'm just saying that this would be an interesting podcast to develop since I, as well as many others, are interested in this topic. Thank you for your in formative podcast. There joy to listen to. Well, Thank you, Tim. It's a joy to get that kind of email. Um okay, so let's start this off by saying we do not recommend you use proxies to get around systems. Uh. That way, there gout that on the table. We can move on

from there. Actually, speaking of of unusual, I guess it's funny that we looked at this subject very differently when we were starting to do the research on it. Yeah,

it's very true. Uh. Pallette, when he thinks of proxies, was thinking of a kind of an administrative system that's used to kind of, uh, well, we'll put limitations on what you can and can't see when you access the web, Whereas I was thinking more along the lines of of what I think Tim was saying, which is that, you know, using certain websites to get around barriers that would otherwise be between you and the content you want to see.

So it's interesting, I guess, uh, I was saying that Pelette's kind of looking at it at the the sort of the law abiding way, and I was looking at it at the the hooligan kind of way. How unusual. Yeah,

it never would have pegged it would. Well, what I was thinking about was personal experience working in corporations where they will put up a in a very advanced firewall which blocks a lot of a lot of cyber attacks and um basically keeps you from going out to UH porn sites or to spend a lot of time on Facebook or your email account and things like that. Basically trying to keep people productive and keep the company from

suffering any harm via the Internet. And in this case, a proxy server would allow you to get information through the firewall, so you you you're essentially bypassing the firewall, but you're bypassing it in ways that the company allows you to bypass it. So it's like, guess you can in fact go to the corporate website UH and to some of our competitors to do research, but you may

not go shopping on Amazon, right. And it kind of helps to sort of give a brief overview of how the Internet works, sort of an Internet infrastructure rundown to sort of understand what we're talking about here. So think of the Internet as a series of servers and clients. It's not a series of tubes that administration is never mind,

So we're talking about clients and servers. The client requests information from servers, and think of all the servers across the world as being nodes, and when you send out a request from a client, it goes out until it reaches the destination where that information resides. Because all the information on the Internet exists on a physical machine somewhere more multiple physical machines sometimes I mean for redundancy's sake,

there are multiple machines with that info. So your your request goes out and then that server serves up the information sends it back to you. It goes through all those nodes, of various nodes to get to you. It may not go through the same ones that your request went through. Uh. They come in packets. The information comes into these little uh, these little packets of information that gets reassembled at your computer and then you've got whatever

it was you sent your request out to get. So a proxy server sits between your client and all the other servers. It is uh, it's it's kind of like a guardian in a way, so it can intercept information being sent out or being brought in too, from the servers to the client or vice versa. And that's where you get filtering, where you can have a proxy server set up with filters that block certain websites, you know, complete access if you want, so just think of it.

It's pretty simple really, It's just a big database of websites saying, you know, don't allow anyone on this side of the proxy server to access these websites. UM. So yeah, very simple kind of concept. Uh, and that's your basic proxy server. Well, and it reminds me actually of Tour. I'm assuming that you're familiar with Tour because what Tour does is, um it's an anonymous web browsing software solution. And uh, it uses the concept that Jonathan was just

talking about about the different nodes. UM. Once you send a request, in your request bounces between computers in different places, and it basically prevents you from being your traffic from being analyzed. So if you are from you know, the United States, and you use Tour to mask your your information, your signal gets bounced around and you might appear to be coming from Sweden, for example, because it is basically

fooling those servers into thinking you're from somewhere else. It's it's very much like those spy movies when they're trying to trace the call. Right, he's calling from Luxembourg. No, wait it's Paris. Wait no, it's Sydney. Australia, same sort of concept, really and uh and what Tim was sort of referring to are these proxy sites that are run by various individuals um where you can log into this proxy site and then from the proxy site you can

then access other websites. So let's say that you are trying to access a video site that's hosted in another country and that country says only only citizens of that country can have access to that site. So you since you're notice is and you know, you get an access denied when you try to access that site directly. You're not thinking of the BBC directly, are you, because they completely do not allow citizens of the United States to

access their web shows. I can neither confirm nor deny that. Well, you know, if you were in Europe, say you might be able to access Hulu, so it would be the same thing. Right, Let's just use a completely theoretical example like that. So let's say that I'm in Europe and I want access Hulu and I can't. Let's stop smirking at any rate, So what what one potential solution? And granted again we're not uh suggesting you do this, but you could find a proxy site that's located within that

country and visit that that proxy site. Then you normally have to fill out a form of some sort and then use that to UH to navigate towards the site you really want to go to. Now, from the perspective of your target site, it looks like you're coming from the proxy. They don't see that you're back in Europe or Atlanta, Georgia, or wherever you happen to really be.

They see your location as being from whatever the proxy site is and UH and so as a result, you may be able to get access to this information that otherwise you could not access. UM. That's the basic idea behind these these proxy avoidance systems. UH. There are some major major issues with proxy avoidance systems that we should

talk about. The first is that unless you are absolutely certain that the person running the site is legitimate, you risk having all of your traffic monitored and recorded and scrutinized by whomever is running that site, because once you fill out that form and that information, you're using their site to to browse around. If they're tracking the information,

they can see what you're doing. So if you access a site where you have to put in a user name and password, there's a chance that they could have access to that information. This is what we in the Internet biz tend to refer to as a bad thing. Yeah, yes, exactly, So, UM, definitely be careful. I, you know, don't recommend using proxy sites on in general. I will not say that I have never used a proxy site. I won't say that I have either, right yeah, yeah, yeah. Was that it

for your your bad things? Yeah, that was it for my bad thing. So that's that's the general low down on on proxy avoidance systems. All right, all right, Well, you know, if you were thinking of it from my point of view, the one where I was talking about your behind the corporate firewall and it's really annoying that you can't get to your Gmail. Um, there were a couple of things that that might work for you. Um.

Now this is an entirely different thing. Keeping your mind, I mean, this is you being restricted by a uh tight firewall. I'm looking for a way to fool the

proxy into letting you through. Well, uh, simple way to do that might be just to add an S to the h T t P. A lot of proxies, as it turns out, corporate proxies are looking for HTTP calling slash slash, and the website you're looking for, well, they may not be looking for a secure version of that site, and you may simply be able to fool the the proxy server into letting you through simply by adding an S to your hdt P. I'm not saying it'll work.

And again, this is another version of it's probably not necessarily a good idea to do this yourself. I mean, you could get caught surfing some site that you shouldn't at work and get fired, So I wouldn't advocate doing that. Um. Also, I know that some people have used, uh, the Google

language tools to get through things. Translating English to English will let people through because it fools the fools the website into thinking it's actually using Google for a useful purpose, until of course they find out and block the English to English translation as part of the u r L.

Because these services use your l's to block. I mean they're they're putting those in specifically, so uh, you know, that's why you can get through to Pandora for two months and then somebody goes too much bandwidth and they cut and they cut you off. You're talking like you speak from experience here, Chris I mean, you're and I just know that some people have done this, and I also know that some people have in order to get

through instant messaging protocols. They find out they download a multi protocol client like a Pigeon or trillion or something like that digsby, and uh, they find out that their their corporate UM I T people have blocked the servers that go through there. Well, actually they're blocking the ports in those cases probably, And if you do a search online, you might find out that there are other ports that

use another server's chat. Servers that use the same protocols, like for example, I c Q might use a number of different servers and ports, and if you, you know, play around with that, you might find out that, well, some of them aren't blocked. Not that I would advocate doing that losing your job, because that would be terrible. That would I would not like that, and I would have corporate parents. Wow. But that's uh, that see that that was the kind of thing I was thinking about.

I do know people who were sty fold by that lack of access to fun and games during work hours. Sure, And I should also point out that proxy sites tend to you know, they tend to come and go pretty quickly because Uh, it turns out that a lot of companies don't like people accessing proxy sites for the same reason that they put the firewall up in the first place. Really, so um, often they'll block access to those. But on the flip side, for everyone that you lose access to,

it seems like two more pop up. Again. It's one of those issues where you definitely have to do your homework and make sure that whichever one you go to is a reputable as far as that goes proxy site. UM. And we should also point out that there are cases where these sites have been very very important for people who are let's say, overseas. Um. It turns out that a lot of journalists in China have used proxy sites in order to get information out of that country because

they're so restrictive. I mean, it's the great our Wall of China is famous for restricting information in and out of that country, and without things like proxy sites, Uh, it would make it much more difficult for information to pass across that firewall. So I mean, it's um, it's it's a sticky issue. It's one that we actually debated on whether or not we should even address this. But then the information is out there and people want to

know about it. And really, I think our our listeners are, on the whole, are very responsible and upstanding lot, wouldn't you say, I'd say so, and they probably realized too that, uh, you know, it's it's fun to talk about some of these things, but when I talk when you talk about losing your job or having your access restricted or you know,

getting into llegal trouble, that's another thing entirely. You don't want to mess with that lightly, right, right, So, so, Tim, We're sure you were just you know, curious, and we hope that we've satisfied your curiosity with this discussion. Did you have any I'm I'm dry, excellent, fantastic, So I'm glad we were able to to to clear that up for you. Tim. If any of you have any questions, you can write us at podcasts at how stuff works dot com. We love getting that email, so definitely right in.

And if you want to learn more about the Internet, the web, how the web is different from the Internet, all of these topics you can find right now at how stuff works dot com. And we'll talk to 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