What is the role of the proxy server?

Proxy Server

A proxy server is an important security feature that works primarily in the dialog layer of the Open Systems Interconnection (OSI) model and thus acts as a firewall. Proxy servers are mostly used to connect to the Internet and intranet (local area networks).

A proxy server is another server between the client and the Web server. With it, the browser does not go directly to the Web server to retrieve the Web page but to the proxy server to send a request, the signal will be sent to the proxy server, the proxy server to retrieve the information required by the browser and sent to your browser.

Because the proxy server consumes a large resource and is time-sensitive, it sometimes fails to open and must try the proxy server several times. Automatically updates the latest available servers on a daily basis.

　　Proxy Server Port

Each host (hosts) on the Internet has a unique address (IP), but the same host may provide more than one service, such as the FTP service, the WWW service, and so on, so that each service occupies one port of that host.

The common ports used by proxy servers are:

HTTP Proxy: 80/8080/3128/8081/9080

Socks Agent: 1080

FTP Agent: 21

Telnet Agent: 23

Warm tip: The presence of proxy servers is generally not public, especially in the Chinese Public Multimedia Information Network (169) on the underground activities! To get a proxy server generally have the following ways: The administrator of the proxy server public or secret communication; Internet users in the chat room or BBS enthusiasm to provide their own search; Obtained from a site that specializes in providing proxy server addresses.

　Knowledge Extension:

1.HTTP Agent: Able to proxy client HTTP access, mainly the proxy browser access to the Web page

2.FTP Agent: Able to proxy FTP software access FTP server on the client

3.RTSP Agent: RealPlayer access to real streaming media server on proxy client

4.POP3 Agent: The Mail software on the proxy client is POP3 to send and receive mail