Premium Essay

Datacom

In: Computers and Technology

Submitted By reverie0730
Words 4600
Pages 19
Definition
Movement of encoded data from one point to another by means of electrical or optical transmission systems. Transfer of information from one computer to another via direct cable connection, over telephone lines, or via air.

History
Smoke signals Sumerian clay tablets (3300 B.C.) Greek messengers/scrolls Telegraph system Telephone system Computers Networking

Science and Technology Information Institute Department of Science and Technology

Overview
Introduction LAN Technologies Network Transports WAN Technologies

Definition

Through a combination of hardware and software, networks permit information and peripherals to be shared efficiently and economically.

Definition
An internetwork is a collection of individual networks, connected by intermediate networking devices, that functions as a single large network. Internetworking refers to the industry, products, and procedures that meet the challenge of creating and administering internetworks.

Figure illustrates some different kinds of network technologies that can be interconnected by routers and other networking devices to create an internetwork.

PC LAN with Host Connection
Network cable plant

Workstation

Host computer Virtual connection to the host

Workstation to file server

File server

Network Architecture
The OSI Model
Implement a layered data communications system Establish a common basis for standards development Qualify products as open by their use of these standards Provide a common reference for standards

Network Architecture
The OSI Model
All People Seem To Need Data Processing
A handy way to remember the seven layers is the sentence "All people seem to need data processing." The beginning letter of each word corresponds to a layer.

—Application layer —Presentation layer —Session layer —Transport layer —Network layer —Data link layer…...

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