They are also used both by children and adults for

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Unformatted text preview: nt and the server. Server software accepts request for service from client software and returns the results of processing the request to the client. The client then manipulates the received results and presents it in the proper format to the user. LAN or WAN or an Internet of Networks Notice that the central feature of a client-server computing architecture is the allocation of application-level tasks between clients and servers. The computers and the operating systems of a client and a server may be different. For example, a client may be a PC running MS-Windows OS, whereas a server may be a mainframe system running Unix OS. In fact, there may be a number of different types of client computers and operating systems and a number of different types of server computers and operating systems in a single client-server computing environment. As long as a particular client and server share the same communications protocol and support the same applications, these lower-level differences are irrelevant. It is the communications protocol that enables client and server to inter-operate. One such standard communications protocol is the TCP/IP. In a client-server computing environment, it is common for one server to use the services of another server, and hence to be both a client and a server at the same time. For example, suppose a client-server computing environment has clients, a file server, and a disk block server. Any client can send a file access request to the file server. On receiving such a request, the file server checks the access rights, etc. of the user but does not actually read/write the file blocks itself. Instead, it sends a request to the disk server for accessing the request data blocks. The disk block server returns to the file server the requested data blocks. The file server then extracts the actual data from the data blocks and returns it to the client. In this scenario, the file server is both a server and a client. It is a server for the clients, but a client for the disk block server. Hence the concept of client and server computer...
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This document was uploaded on 04/07/2014.

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