Proxy Servers

[A_Bails]

Can someone give me a brief explination of what proxy servers are or point me to a website that offers some information about this topic. It's just for my own personal curiosity. I always hear them mentioned and have no idea what they are.

[Statica]

A proxy server is in essence basically a type of firewall that controls &/or monitors outbound traffic. Its somewhat of a "requester" and transmitter. Basically 2 categories of Proxy servers, application proxies .. these "help" the applications that require the network make the appropriate connections. For example if you have a proxy server at work to connect to the internet. Say you typed www.pcmech.com on your browser; your browser (the application) requests www.pcmech.com from the proxy server - the proxy server requests the information from the PCMech server and then passes it on to you. Or you could have a SOCKS proxy server that basically "rewires" the ports for one that the network deems necessary. For example, if MSN Messenger typically requires port 789; the SOCKS server would perhaps "reroute" data on port 789 to port 123; MSN talks to port 789 on the internal network, but when the information goes out the SOCKS server would use port 123.

There are tons of reasons to use a proxy server, and why they are so common:
- they conserve bandwidth .. say you have a proxy server at work; and at lunch time 12 people request www.pcmech.com .. the proxy server also serves as a cache, so basically the first person's request makes the proxy server store a lot of the content from pcmech.com on its cache and the remaining 11 can just get most of it from the proxy
- they virtually increase speeds- see above reasoning
- the (relatively) protect the IP addresses of the people networked behind, obviously if its the proxy server connecting to a webpage etc; then the proxy server's IP address is the one that is sent out.
- and perhaps most importantly, they can efficiently log the activity of a user
- can also work as a filter, by denying access to content that would violate the service provider's agreements.


HTH