Client/server programming in local area networks
Increasingly the business user requires immediate access to remote stock markets data, videoconferencing and electronic document interediting, which can be achieved by digitalisation, allowing electronic storage, process and transmission of the data. One of the main purposes of network programming is to develop applications that provide services to independent computer systems. Following the original design of BSD engineers, the network services provided at application level and available as user commands which come with UNIX systems are implemented as daemons, sleeping processes running in the server host that are invoked by client processes from remote workstations connected to the TCP/IP network. In the JRC, the members of the team involved in the development of SL, a distributed multi-user electronic document management system, have needed to exploit the network programming mechanisms provided by SunOS 4.1.1 implementation of the UNIX system. This paper gives a perspective of such tools and presents a simple example of client/server application. On the initiative of the client, an association - or typed communication channel - is established between the client and the server processes. An association consists of a uniquely identified tuple: <protocol, local machine address, local port, remote machine address, remote port>. The machine address and the port number constitute the communication end-point identifier, while the protocol is the type of the channel that determines the semantics of the raw data transfer between both processes.
Bibliographic Reference: Paper presented: Networking negli anni '90, Roma (IT), Nov. 24-26, 1992
Availability: Available from (1) as Paper EN 37277 ORA
Record Number: 199310092 / Last updated on: 1994-11-29
Original language: en
Available languages: en