Anonymity of Proxy

Anonymity of Proxy

The exchange of information in Internet is made by the "client - server" model. A client sends a request (what files he needs) and a server sends a reply (required files). For close cooperation (full understanding) between a client and a server the client sends additional information about itself: a version and a name of an operating system, configuration of a browser (including its name and version) etc. This information can be necessary for the server in order to know which web-page should be given (open) to the client. There are different variants of web-pages for different configurations of browsers. However, as long as web-pages do not usually depend on browsers, it makes sense to hide this information from the web-server.

What your browser transmits to a web-server:
a name and a version of an operating system
a name and a version of a browser
configuration of a browser (display resolution, color depth, java / javascript support, ...)
IP-address of a client
Other information

The most important part of such information (and absolutely needless for a web-server) is information about IP-address. Using your IP it is possible to know about you the following:
a country where you are from
a city
your provider?s name and e-mail
your physical address

Information, transmitted by a client to a server is available (accessible) for a server as environment variables. Every information unit is a value of some variable. If any information unit is not transmitted, then corresponding variable will be empty (its value will be undetermined).

These are some environment variables:

REMOTE_ADDR ? IP address of a client

HTTP_VIA ? if it is not empty, then a proxy is used. Value is an address (or several addresses) of a proxy server, this variable is added by a proxy server itself if you use one.

HTTP_X_FORWARDED_FOR ? if it is not empty, then a proxy is used. Value is a real IP address of a client (your IP), this variable is also...