Data Communication Network

Data Communication Network

331: STUDY DATA COMMUNICATIONS AND NETWORKS

331: STUDY DATA COMMUNICATIONS AND NETWORKS

1. Discuss computer networks (5 hrs)

2. Discuss data communications (15 hrs)

331.2: Discuss Data Communications PERFORMANCE STANDARD

◦ Given a network system, identify and illustrate the different data communications components clearly

Objectives:◦ Define elements of a communication system◦ Define data communications◦ Discuss various types of transmission media and

their characteristics◦ Discuss encoding of information tor transmission◦ Discuss types of signal & their characteristics◦ Relate data capacity of a channel and bandwidth◦ Classify media based on bandwidth◦ Discuss channel organization

SKILL AREA 331.2.1

Define elements of a Communication

System

Define elements of a Communication System The following are the basic requirements for

working of a communication system.1. A sender / transmitter (source), which

creates the message to be transmitted.2. A medium that carries the message.3. A receiver (sink), which receives the message.

Define elements of a Communication System

Basic requirement for working of a communication system

Define elements of a Communication System In data communication four basic terms are

frequently used. They are:◦ Data: A collection of facts in raw form that

become information after processing.◦ Signals: Electric or electromagnetic encoding of

data.◦ Signaling: Propagation of signals across a

communication medium.◦ Transmission: Communication of data achieved by

the processing of signals.

Define elements of a Communication System The basic components of communication

system are:◦ Input / Data Source (where the data originates)◦ Transmitter (device used to transmit data)◦ Transmission Medium (cables or non cable)◦ Receiver (device used to receive data)◦ Output / Destination (where the data will be

placed)

Define elements of a Communication System

The input produced by a source must be converted to a form suitable for the particular type of communication system.

Example: In electrical communications, speech waves are converted by a microphone to voltage variation.

Define elements of a Communication System

Define elements of a Communication System The transmitter processes the input signal to

produce a suitable transmitted signal suited to the characteristics of the transmission channel.

The Medium can have different forms: The atmosphere (or free space), coaxial cable, fiber optic, waveguide, etc.◦ The signal undergoes some amount of degradation

from noise, interference and distortion

Define elements of a Communication System The receiver’s function is to extract the

desired signal from the received signal at the channel output and to convert it to a form suitable for the output.

◦ Other functions performed by the receiver: amplification (the received signal may be extremely weak), demodulation and filtering

Define elements of a Communication System Example: Khaliq uses microphone to

sing a song. Input / data source: voice The input (in analogue) will be

converted to a digital form. The transmitter will send the digital

signal to the receiver (speaker) via a medium/channel (wire).

Discussion Example of data communication: How is the

“Touch n Go” functioning?

Question?