Network Database Junction - java project

In today’s world, Internet is playing crucial role. Everyone need Internet for Information gathering, communication and entertainment. A system can access Internet only if it has dedicated Internet connection. Any client system in the network (LAN) can’t access Internet without a dedicated Internet Connection to each system; even the server has an Internet connection. One more problem is, if the system is directly connected to Internet, the system can be attacked by the viruses and worms in the Internet. These problems can be overcome by the introduction of Proxy server into the system which is connected to Internet.

Some home networks, corporate intranets, and Internet Service Providers (ISPs) use proxy servers (also known as proxies).

This project has mainly three modules.

♣ Connection sharing

♣ Caching

♣ Filtering

The Connection sharing module provides shared Internet Access. A single Internet connection is proxied and is shared among multiple clients. That is, rather than giving each client system an individual direct Internet connection, a single connection is shared and all internal connections can be tunneled through the proxy system which is connected to the Internet.

The caching module stores all the requested web pages in a local disk cache. Whenever a client requests a web page, the cache manager checks that page in the local cache, if it is available then the page is sent to the requested client, otherwise a request is made to the parent proxy in child proxy server mode. The server sends requests directly to the web server if it is started as main proxy server. After receiving the response, the page is cached in local cache and then it is forwarded to client.

The filtering module filters all the requests made by the client. In this proxy server the filtering module has sub modules named site filtering and word filtering. In site filtering, whenever a client requests a web page, first the page is checked with in the restricted sites domain, if it is not in the restricted domain, then the request is forwarded to the cache manager. In word filtering, a page downloaded from parent proxy or web server is checked against the restricted words domain. If the words in the downloaded page are matched with the words in the restricted list, a warning message is forwarded to the client, otherwise a copy of the page is forwarded to the client and another copy is forwarded to the cache manager. The filtering feature makes the proxy server to act as a firewall.