Sharing Internet through a proxy

Proxy servers let you share a single Internet connection among multiple PCs. Additionally, they also provide multitude of other benefits

Most small and medium sized offices today have perhaps only one Internet connection. In addition, because of the limited infrastructure, one can connect only a single PC to access the Internet at any given time. A simple but expensive solution would be to install a second phone line and buy a second modem.

A viable alternative to get more than one PC online at your office or home would be to share your single Internet connection. This can be achieved through various means such as using hardware solutions such as a router or a proxy server.

What is a proxy server?
A proxy server is a kind of buffer between your computer and the Internet resources you are accessing (e.g. websites or FTP archives). The data you request come to the proxy first, which then transmits the data to your PC.

Basically a proxy server sits between a client program (usually a Web browser) and some external server (a server on the Web). The proxy server can monitor and intercept any and all requests being sent to the external server or that comes in from the Internet connection. This positioning gives the proxy server three functions: filtering requests, improving performance, and sharing connections.

What does a proxy server do?
The main job of a proxy server is its security function. Proxy servers can inspect all traffic (in and out) over an Internet connection and determine if there is anything that should be denied transmission, reception, or access. Since this filtering cuts both ways, a proxy server can be used to keep users out of particular websites (by monitoring specific URLs) or restrict unauthorized access to the internal network by authenticating users.

Since proxy servers handle all communications, they can log everything the user does. For HTTP (Web) proxies this includes logging every URL. For FTP proxies this includes every downloaded file.

The other functional aspect of a proxy server is improving performance and is called proxy server caching. In simple terms, the proxy server analyzes user requests and determines which, if any should have the content stored temporarily for immediate access. Cache management is a big part of many proxy servers, and it is important to consider how easily the cache can be tuned and for whom it provides the most benefit.

Some of the proxy servers, particularly those targeted at small office/home office users, provide a means for sharing a single Internet connection among a number of workstations. While this has practical limits in performance, it can still be a very effective and inexpensive way to provide Internet services, such as e-mail, throughout an office.

Kinds of Proxy servers
The various kinds of proxy servers are:

Departmental proxies
Departmental proxies are firewalled proxy servers that are chained to other proxy servers in order to impose different restrictions on different user groups in a company.

Private proxies
They are proxy servers that are on an individual client's computer. One of the many advantages of using a private proxy server is SSL Tunneling, although many browsers such as Netscape and Internet Explorer support SLL in the software package.

Reverse Proxies
These are proxy servers that are set up to "fool" users into thinking they are connecting to a source server. Reverse Proxy Servers are generally used for:

So why should you use a proxy?
You can use a proxy server if you wish to restrict the sites she/he is viewing. You can use it to protect yourself, to hide your IP to prevent hackers from accessing information about you while online. They will only get the proxy server's IP. Proxy servers are not hard to set up, you just need to configure your browser to connect through it.

Mahesh Rathod can be reached at rathodmp@hotmail.com