LESSON 1 FCK

Data Communication

Data Communication

________: is the transfer of data or information between a source and a receiver.

Data Communication

________ is the exchangeof data (in the form of 0s and 1s) between two devices (computers) via some form of the transmission medium.

Data:

information that is stored in digital form

Information:

is defined as knowledge or intelligence

Network:

is a set of devices interconnected by media links

Internet:

a global computer network providing a variety of information and communication facilities, consisting of interconnected networks using standardized communication protocol

(1753)

A proposal was submitted to a Scottish magazine suggested running a communications line between villages comprised of 26 parallel wires, each wire for one letter of the alphabet

(1833)

Carl Friedrich Gauss developed an unusual system based on a five-by-five matrix representing 25 letters (I and J were combined).

(1832)

Samuel F.B. Morse invented the first successful and practical data communications system which he called the Telegraph. With the telegraph, dots and dashes are transmitted across a wire through electromechanical induction. He also developed the first practical data communications code which we all know as the Morse Code.

(1840)

) Morse secured an American patent for his telegraph

(1844)

The first telegraph line was established between Baltimore and Washington D.C “What hath God wrought!”

(1849)

the first slow-speed telegraph printer was invented

(1860)

the first high-speed (15-bps) printers were available.

(1874)

Emile Baudot invented a telegraph multiplexer which allowed signals up to six different telegraph machines to be transmitted simultaneously over a single wire.

Samuel F.B. Morse

invented the first successful and practical data communications system which he called the Telegraph. With the telegraph, dots and dashes are transmitted across a wire through electromechanical induction. He also developed the first practical data communications code which we all know as the Morse Code.

Emile Baudot

invented a telegraph multiplexer which allowed signals up to six different telegraph machines to be transmitted simultaneously over a single wire.

(1876)

Alexander Graham Bell invented the telephone.

(1899)

Guglielmo Marconi succeeded in sending radio telegraph messages.

(1920)

First commercial radio stations were installed, allowing the transmission of information across large spans of water.

(1940)

Bell Laboratories developed the first special-purpose computer using electromechanical relay.

Bell Laboratories

developed the first special-purpose computer using electromechanical relay

(1951)

The UNIVAC was the first mass produced electronic computer, built by the Remington Rand Corporation

Universal Automatic Computer

UNIVAC stands for?

1960s

batch processing systems were replaced by on-line processing systems.

1970s

microprocessor-controlled microcomputers were introduced.

1980s

Personal computers became an essential item

(1968)

The AT&T operating tariff allowed only equipment furnished by AT&T to be connected to AT&T lines

(1969)

Internet began to evolve at the ARPA.

Advanced Research Projects Agency

ARPA stands for

(1970)

ARPANET was formed to connect sites around the US.

(1991)

The World Wide Web became publicly available

WHAT ARE THE DATA COMMUNICATIONS NETWORK ARCHITECTURE

Data Communication Network,

Network Architecture

Data Communication Network

- is any system of computers used to transmit and/or receive information between two or more locations.

Network Architecture

is a set of equipment, transmission media, and procedures that ensures that a specific sequence of events occurs in a network in the proper order to produce the intended results

: Current Networks

Legacy Networks

Legendary Networks

Network and Network Protocols fall into three General Classifications

Current Networks

include the most modern and sophisticated networks and protocols available.

Legacy Networks

-A network or a protocol becomes a legacy when no one really wants to use it, but for some reason it just won’t go away. Legacy networks are mostly proprietary to individual vendors.

Legendary Networks

-when an antiquated network or protocol finally disappears, it becomes legendary.

Broadcast Network

Point-to-point Network

Computer Networks can be classified in two different ways

Broadcast Network

-All stations and devices on the network share a single communication channel.

Point-to-point Network

-It only has two stations. No addresses are needed. All transmissions from one station are Intended for and received by the other station.

Protocols

-are set if customs, rules, regulations dealing with formality or precedence, such as diplomatic protocol or military protocol.

Data Communication Protocols

are sets of rules governing the orderly exchange of data within the network or a portion of the network. Can either be Connection Oriented or Connectionless.

Syntax

refers to the structure or format of the data within the message, which includes sequence in which the data are sent.

Semantics

refers to the meaning of each section of data.

Data Communications Standards

-are guidelines that have been generally accepted by the data communication industry. (Proprietary or Open)