Abstract
Under Unix circumstance, this subject inroduce the exploitation of TCP/IP developing several procedure modules, Construction peer-to-peer model.
The design is constituted by a client ,a server and a transfer server. Client send download request to the server.The server inquiries the database then return the address information of related transfer server . Client server connects to the transfer server based on the return address information for data downloadding . Server control client connectting to transfer server then to sent data and piece them together and so on. The server here is the role of a bridge.It is not the main carrier of the data . Server complete collectting information, inquiring and state control function. Other treatment relies mostly on the client and transfer server themselves. It’s fully embodies the subject that the mainstay of the network is the client not server. The main issue is the use of the information collection and dissemination in the subject.
There are thousands of clients and transfer servers at least in a mature network.This paper only focus on how to use socket to communicate between the programs in Unix environment. As for the middle of information gathering, state inquiries and control process replaced by some simple procedures to achieve similar functions..