learn about proxy

What is a Proxy Server?
A proxy server is a kind of buffer between your computer and the Internet resources you are accessing. The data you request come to the proxy first, and only then it transmits the data to you. I know many are looking for IP Maskers or Scramblers, but honestly, it aint real easy for the simple fact that any website that you visit needs your IP to send the info packets too. If its scrambled, you will get alot of errors and crazy redirects My solution? Read on........... for a good list of Proxy servers try here>> http://www.multiproxy.org/

Why do I need to use proxy servers?
Transfer speed improvement. Proxy servers accumulate and save files that are most often requested by thousands of Internet users in a special database, called “cache�. Therefore, proxy servers are able to increase the speed of your connection to the Internet. The cache of a proxy server may already contain information you need by the time of your request, making it possible for the proxy to deliver it immediately.
Security and privacy. Anonymous proxy servers that hide your IP address thereby saving you from vulnerabilities concerned with it.
Sometimes you may encounter problems while accessing to web server when server administrator restricted access from your IP or even from wide IP range (for example restricting access from certain countries or geographical regions). So you try to access those pages using an anonymous proxy server.

What is a public proxy server?
It is a proxy server which is free and open for everybody on the Internet. Unfortunately most of them are not anonymous.
Free service trying to provide list of public HTTP proxy servers. Usually provide small list of proxies with low percent of functioning servers due to hosting restrictions on CPU time (they simply can't allow themselves to check many proxies every second especially in parallel).

The Solution?
When using an anonymous proxy server you don’t give a anybody chance to find out your IP address to use it in their own interests. If there is a need to make an (inner) proxy connect to the outside world via another (outer) proxy server, you can use the same environment variables as are used to redirect clients to the proxy to make inner proxy use the outer one:
http_proxy
ftp_proxy
gopher_proxy
wais_proxy
E.g. your (inner) proxy server's startup script could look like this:
#!/bin/sh
http_proxy=http://outer.proxy.server:8082/
export http_proxy
/usr/etc/httpd -r /etc/inner-proxy.conf -p 8081

This is a little ugly, so there are also the following directives in the configuration file:
http_proxy http://outer.proxy.server/
ftp_proxy http://outer.proxy.server/
gopher_proxy http://outer.proxy.server/
wais_proxy http://outer.proxy.server/



Different Types of Proxy scripts:

PHProxy - PHProxy is very fast, and doesn't use much CPU and memory of the server as compared to others. However, has some drawbacks inretaining the cookies and login methods of newer websites.

CGIproxy - CGIproxy is slower than PHProxy, but is more secure and feature rich. It has better support for javascript, and can log into most of the sites compared to PHProxy. On the other hand CGI proxies are extensively resource hunger and consumes lots of RAM

Glype - Glype is an intermiediate proxy with a balance between speed and performance. [not much popular]

Zelune - Zelune is a new proxy script and slightly gaiing popularity as loading time of pages is very quick. Zelune proxy uses CURL to fetch the pages.


Surrogafier - A fairly new proxy script. Offers some advanced options, but does not support ssl.

BBlocked - BBlocked is a recently updated proxy script. One of its best features is the built in templating system.


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 added by a proxy server if you use one.

HTTP_ACCEPT_LANGUAGE ? what language is used in browser (what language a page should be displayed in)

HTTP_USER_AGENT ? so called "a user?s agent". For all browsers this is Mozilla. Furthermore, browser?s name and version (e.g. MSIE 5.5) and an operating system (e.g. Windows 98) is also mentioned here.

HTTP_HOST ? is a web server?s name

This is a small part of environment variables. In fact there are much more of them (DOCUMENT_ROOT, HTTP_ACCEPT_ENCODING, HTTP_CACHE_CONTROL, HTTP_CONNECTION, SERVER_ADDR, SERVER_SOFTWARE, SERVER_PROTOCOL, ...). Their quantity can depend on settings of both a server and a client.

These are examples of variable values:

REMOTE_ADDR = 194.85.1.1
HTTP_ACCEPT_LANGUAGE = ru
HTTP_USER_AGENT = Mozilla/4.0 (compatible; MSIE 5.0; Windows 98)
HTTP_HOST = www.webserver.ru
HTTP_VIA = 194.85.1.1 (Squid/2.4.STABLE7)
HTTP_X_FORWARDED_FOR = 194.115.5.5

Anonymity at work in Internet is determined by what environment variables "hide" from a web-server.

If a proxy server is not used, then environment variables look in the following way:

REMOTE_ADDR = your IP
HTTP_VIA = not determined
HTTP_X_FORWARDED_FOR = not determined

According to how environment variables "hided" by proxy servers, there are several types of proxies
Transparent Proxies

They do not hide information about your IP address:

REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = your IP

The function of such proxy servers is not the improvement of your anonymity in Internet. Their purpose is information cashing, organization of joint access to Internet of several computers, etc.
Anonymous Proxies

All proxy servers, that hide a client?s IP address in any way are called anonymous proxies

Simple Anonymous Proxies

These proxy servers do not hide a fact that a proxy is used, however they replace your IP with its own:
REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = proxy IP

These proxies are the most widespread among other anonymous proxy servers.

Distorting Proxies

As well as simple anonymous proxy servers these proxies do not hide the fact that a proxy server is used. However a client?s IP address (your IP address) is replaced with another (arbitrary, random) IP:

REMOTE_ADDR = proxy IP
HTTP_VIA = proxy IP
HTTP_X_FORWARDED_FOR = random IP address
High Anonymity Proxies

These proxy servers are also called "high anonymity proxy". In contrast to other types of anonymity proxy servers they hide a fact of using a proxy:

REMOTE_ADDR = proxy IP
HTTP_VIA = not determined
HTTP_X_FORWARDED_FOR = not determined

That means that values of variables are the same as if proxy is not used, with the exception of one very important thing ? proxy IP is used instead of your IP address.
Summary

Depending on purposes there are transparent and anonymity proxies. However, remember, using proxy servers you hide only your IP from a web-server, but other information (about browser configuration) is accessible!