Many people use proxies for a variety of different reasons. Some use them for security, basically using the proxy server to hide their identity(and IP address) from the web site they are visiting. Others use them to bypass blocks which are based on IP addresses. these could include if your IP address is banned from a forum or site for some reason or when it’s blocked because of it’s location . This is surprisingly common and major sites like the BBC, Hulu, ABC and YouTube block access to millions based on their location.
So it’s not surprising that so many people use proxies for these reasons, but most people don’t have much of an idea of how they actually work. For instance if you start filtering all your traffic through a proxy then you are effectively expecting it to handle all sorts of different protocols. If you filter through a foreign country perhaps through a German or Turkish proxy or maybe a UK TV VPN then you’ll also appear to be located here.
So How Does A Proxy Handle all These Protocols?
Well to be honest some don’t, if you use any of the free ad financed web proxies you see online they’ll frequently fall over or fail to connect. But a well configured proxy should be able to handle most of the protocols you send through it. This is because the proxy operates at the Application Layer of the OSI Model.
This means that to some extent a proxy server can actually understand what is happening. The proxy has two basic ways of dealing with the traffic – it can either proxy or tunnel the protocol. If it understand the protocol you can do neat things like filter it, perform advanced logging and even operate access control to deny or allow access.
If the proxy doesn’t understand a protocol then it will just act as a dumb tunnel and forward and receive the data between the client and server. For instance you’ll find that the vast majority of web based proxies have no support for SSL as they don’t understand it.
Proxies will normally be able to handle protocols that also operate at the application level like HTTP, Gophur and FTP for instance. When using a proxy server though remember you are entrusting it with all your personal data that you are sending through your browser – take care using proxies that you know nothing about. The reality is that setting up a free proxy server is a great way of stealing peoples usernames, passwords and other identity related information.