Data CommunicationData CommunicationPrepared By: MIHE IT DepartmentPrepared By: MIHE IT Department

DEFINITION of DATA DEFINITION of DATA COMMUNICATIONCOMMUNICATION

“Data Communication is the exchange of Information from one entity to the other using a Transmission Medium”

LOCAL and REMOTE LOCAL and REMOTE CommunicationCommunication

LOCAL– Communicating devices are present in the same

building or a similarly restricted geographical area.– When the source and destination are in the same

network

Data Communication Data Communication Definition (Modified)Definition (Modified)

“Data Communication is the exchange of data (in the form of 0’s and 1’s) between two devices (computers) via some form of the transmission medium.”

LOCAL and REMOTE LOCAL and REMOTE CommunicationCommunication

REMOTE– Communicating devices are present farther apart.– When the source and destination are in the different

network.

Data Communication Data Communication SystemSystem

For Data Communication to occur, communicating devices must be a part of a system made up of some specific kind of hardware and software. This system is known as

“DATA COMMUNICATION SYSTEM”

Effectiveness of Data Effectiveness of Data Comm. SystemComm. System

Delivery (the data you send and it is received to the destination)

Accuracy (what you send the same is received and there is no error)

Timeliness (the data reach to the destination in good time).

Components of a Simple Components of a Simple Data Communication Data Communication

SystemSystem

Components of a Data Components of a Data Communication SystemCommunication System

A Data communication system is made up of 5 components: Message Sender Receiver Medium Protocol

Components of a Data Components of a Data Communication Communication

SystemSystemMessage: It is the data which the source send to destination

Sender: a device which sends the data. Receiver: a device which receive the data. Medium:

the path through which the data is traveling from sender to receiver.

Protocol:Set of rules that govern communication or set of rules

that makes the communication both possible and efficient.

Transmission mediaTransmission media

Guided media unguided media

Twisted pair cable optical fiber water, air, vacuum coaxial cable

Shielded twisted pair Thick net Single mode Unshielded twisted pair Thin net Multimode

Transmission MediaTransmission Media

Medium Speed Cost

Twisted Wire 100bps-1000Mbps Low

Coaxial Cable 56Kbps-200Mbps Low

Fiber Optic Cable 500Kbps-10Gbps High

Wire Based MediaWire Based Media

Twisted-pair cable Most common LAN cable Called Cat5 or 100BaseT Four pairs of copper cable twisted May be shielded from interference

(polyester/aluminum) Speeds range from

1 Mbps to 1000 Mbps Twisted to remove the cross talk UTP and STP are types of twisted pair

Coaxial cable Also called coax Similar to cable TV wire One wire runs through cable Shielded from interference Speeds up to 200 Mbps Nearly obsolete Expensive than Twisted pair

Wire Based MediaWire Based Media

Wire Based MediaWire Based Media Fiber-optic cable

Data is transmitted with light pulses (signals)

Glass strand instead of cable Protected to interference Very secure Hard to work with Speeds up to

10 Gbps

A Simple data A Simple data communication Modelcommunication Model

SourceA device which generate data

TransmitterIs a device which takes data from source and convert it into a form

that is transmutable over transmission media

Transmission systemIs the path available between source and destination and through

which the data can travel.

Receiver Is a device that takes data from transmission system and convert it

into a form that is understandable by computer.

Destination It is the final point of communication.

EXAMPLE – Electronic EXAMPLE – Electronic MailMail

Key Data Communication Key Data Communication TerminologyTerminology

Network: interconnected group of computers and communication devices. Can share the resources Can share the data

Node: a network-attached device that can send and receive the data. E.g. Computer, router, Switch.

Key Data Communication Key Data Communication TerminologyTerminology

Link: links are the path that connects adjacent nodes

Path: end-to-end route within a network

Circuit: the conduct over which data travels. Circuit is the path for current flow. Circuit can be open or close. Open circuit means that there is a break in the wire and current can not pass. A close circuit means that circuit is complete and current can pass

Key Data Communication Key Data Communication TerminologyTerminology

Packetizing: dividing messages into fixed-length packets prior to transmission over a network’s communication media

Routing: determining a message’s path from sending to receiving nodes

Router: router is the device that perform the function of routing and switching

BandwidthBandwidth

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Measuring BandwidthMeasuring Bandwidth

What Are The Components Of A What Are The Components Of A Network ?Network ?

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