Distributed elements

Abstract

The following chapters cover the theory of distributing data and processing over a network, thus we need to understand the main principles involved in data distribution. The main principle is the concept of peer -to-peer systems, and client -server systems. A server is a system that provides a particular service (such as remote login, or file services) to a client. The server must wait on connections from clients. A peer-to-peer network works on cooperation, where peer computers share resources. Small networks (typically with fewer than 10 computers) normally work best with a peer-to-peer network, and larger networks work best with a client-server architecture. It must be noted that client-server and peer-topeer architectures can easily co-exist together, and many networks operate this way. A good example is that a computer will use a client-server architecture when contacting a WWW server, but it might use a peer-to-peer architecture when it is sharing a printer with its neighbour. The Internet supports many server applications, including remote login (telnet), remote file transfer (ftp), electronic mail transfer (smtp), domain name services (dns), and so on.