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Proxy Server Definition

Proxy Server Definition

How do I open a link via a proxy sever?

Asked by: Guest | Views: 82
Total answers/comments: 4
Guest [Entry]

"When you attempt to access, say, google, your browser goes through several steps:

Firstly, it doesn't really know what google.com is, so it asks it's more knowledgeable friend, the DNS server. He/She knows who google is (they know EVERYBODY. Life of a party, seriously), so they check their records and give the browser google's 'number' (their IP address (74.125.53.100, in this case)

Right, now you know their number, so 'ring them' (make a connection), and say hello (ask for some content). Google then sends you their homepage, which your browser looks at, then sends off to the HTML rendering guys. They put all the tags and words and stuff together into something that looks like it should. (Sometimes the HTML guys come across some javascript, they ignore that and don't put it in the page, then the Javascript guys deal with it later).

When you use a proxy server, instead of asking the DNS server who google is, you tell the proxy you want to speak to google, so THEY ask who google are, ring them up, and get their details, and then just send you the data for the HTML and javascript guys. The upshot of this is that if your DNS server really doesn't like google, and you don't know any other DNS servers, or can't ask another DNS server for whatever reason, Mr. Proxy can still find google for you.

How you use a proxy depends on what it is. Web-Based proxy services have a form for you to type in the URL, then they go and get the content, but other proxy servers are configured in your browser, and it automatically asks the proxy instead of the DNS guys without you having to do any more configuration. Step one to using one is finding one, a web-based one is straightforward, and in FF you'd go to options/advanced/network/configure how firefox connects to the internet/ to set up a different proxy.

In many workplaces you may already be using a proxy service without you knowing, these could be used to reduce the number of times the DNS server is queried (500 PCs all trying to reach google? Why not cut your DNS requests by 500 by getting the proxy to remember who google is?), filter dangerous or inappropriate content (Can't get viruses as easily if they're blocked from contacting you, and you can't slack off if your favourite flash games site is blocked :)), or as Arjan correctly states below, to trick region-locked services such as Hulu into thinking you live somewhere it can be used. Privacy is another concern, but you're better off using a service that allows you to encrypt the content with SSL in that case (Though there is a lot of overlap, there)."
Guest [Entry]

"A proxy server is generally system which offers a system's service representatively. This may be used for example to gain more performance (caching), to have full control over the data which passes to the service (maybe a reverse proxy or ALG) or to balance the load of a network.

You can use your web browser to surf a web site through a web proxy (HTTP or SOCKS, I guess). The exact configuration depends on the web browser. Which web browser do you want to use?"
Guest [Entry]

"Is this a one-off problem, or do you need to access certain sites via proxy?

PAC files were created for this. Please comment w/ more info, and I will explain further."
Guest [Entry]

There are proxies, like IP:Port proxies, which you enter in the browser settings. These channel your traffic through that computer. There are other types of proxies, like web proxies, which you can just enter the link and it will be displayed on that website for you.