Computer Network

Jose Perez

2010-0235

English for Engineer VI

Computer Networks

Index
Theme Page

* Introduction------------------------------------------------------------------------------------------3
* Definition of Network Computer-------------------------------------------------------------- 4
* History-------------------------------------------------------------------------------------------------5
* Properties---------------------------------------------------------------------------------------------6
* Communication Media----------------------------------------------------------------------------7
*Communication protocols and network programming------------------------------------9
* Scale---------------------------------------------------------------------------------------------------11
* Organizational Scope------------------------------------------------------------------------------14
* NetworkTopology----------------------------------------------------------------------------------15
* Conclusion--------------------------------------------------------------------------------------------17
* Glossary-----------------------------------------------------------------------------------------------18

Introduction
The fundamental purpose of computer networks is to provide access to shared resources, most notably printers and data storage (both disk drives and tapedrives). Local Area Networks (LANs) involve several primary components:
* Network interconnection (for example, copper wire, fiber optic cable, infrared, or radio).
* Network Interface Circuitry (NIC) in the individual personal computers, connected to the network. This circuitry may be part of the system motherboard or it may be on a separate plug-in card.
* The shared resourcesthemselves, each with their own NIC connected to the network.
* Software on the individual personal computers that uses the NIC to access the shared resources. This software is typically arranged to present the appearance to the rest of the operating system that these resources are directly connected. In the jargon, "emulating local disks and printers."
* Software on the shared resource thatcoordinates with the software on the individual machines to provide access to the shared resources for the users of the multiple individual personal computers. This software is typically running on a computer system ("the server") to which the shared resources are directly attached, and is a multi-user operating system.
The most common case is for the server to be the same sort of personal computerhardware as the individual personal computers on the network (Intel or Macintosh). In this case, the operating system is called a "network operating system" to emphasize the difference from the single-user operating system of the personal computer. Novell is perhaps the most striking example of this approach.
Alternatives include a laser printer with a microprocessor-controlled NIC that runssoftware to manage the printer as a shared resource (e.g., the JetDirect cards for HP laser printers), and using a full-blown general-purpose multi-user server, with an operating system like VMS or UNIX. Windows NT Server is perhaps more accurately described as an example of this latter class.

Definition of Computer Networks
A computer network is a group of computers that shares information acrosswireless or wired technology. Computer networks used to only be available for corporations but they are affordable for small businesses and individuals. Computer networking requires two computers, a protocol and the hardware to connect them.

Where at least one process in one device is able to send/receive data to/from at least one process residing in a remote device, then the two devices are...