DATA COMMUNICATION AND

NETWORKS

Lecture: 1

Instructor Mazhar Hussain

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DATA COMMUNICATION AND

NETWORKS

Blog

https://mazharhussainatisp.wordpress.com

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COURSE OUTLINE

The course will consist of :

16 lectures

2 assignments

2exams (1 midterm and 1 final)

Grading Criteria: One Midterm: 25 %

Final Exam: 50%

Assignments /Quizz/Presentation: 15%

Attendance : 10% 3

TEXT BOOKS

“Data Communications and Networking” 4th Edition by

Behrouz A. Forouzan

“Data and Computer Communication” 6th Edition by

William Stallings

Computer Networks (5th Edition) by Andrew S.

Tanenbaum

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TODAY AGENDA

Data Communication

Brief History of Communication

Data Communication System

Key Data Communication Terminology

Effectiveness of Data Communication System

Components of Data Communication System

Key Data Communication Terminologies

Why Networks? And types of Networks

Network Criteria and Applications

Protocols, Elements and Applications of Protocols5

DATA COMMUNICATION

DEFINITION

“Data Communication is the exchange of

Information from one entity to the other using a

Transmission Medium”

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DATA COMMUNICATION

“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.”

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LOCAL AND REMOTE COMMUNICATION

LOCAL

–Communicating devices are present in the

same building or a similarly restricted geographical area

REMOTE–Communicating devices are

present farther apart

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DATA COMMUNICATION SYSTEM

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

“DATACOMMUNICATION SYSTEM”

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EFFECTIVENESS OF DATA COMM. SYSTEM

Effectiveness depends uponthree

fundamental characteristics:

Delivery

Accuracy

Timeliness

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DATA COMMUNICATION

SYSTEM

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DATA COMMUNICATION SYSTEM

A Data communication system is

made up of 5 components:

Message

Sender

Receiver

Medium

Protocol12

MESSAGE TYPES

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A Complex Data Comm.

System

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KEY DATA COMMUNICATION

TERMINOLOGY

Session: communication dialog

between network users or applications

Network: interconnected group of

computers and communication devices

Node: a network-attached device 15

KEY DATA COMMUNICATION

TERMINOLOGY

Link: connects adjacent nodes

Path: end-to-end route within a network

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KEY DATA COMMUNICATION

TERMINOLOGY

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 nodes17

NETWORK

A “Network” is a set of

devices (Nodes) connected

by Communication Links

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WHY NETWORKS?

Point to point communicationnot

usually practical

–Devices are too far apart

–Large set of devices would need

impractical number of connections19

WHY NETWORKS?

Solution is to connect all devicesto a central system known as a NETWORK

Two Main Classes ofNetworks

–Local Area Networks (LANs)

–Wide Area Network (WANs)

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NETWORK CRITERIA

Data

Communication

Network Criteria

Performance Reliability Security

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NETWORK CRITERIA

Performance

–Number of Users

–Type of Transmission Medium

–Hardware

–Software22

NETWORK CRITERIA

Reliability

–Frequency of failure

–Recovery Time after Failure

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NETWORK CRITERIA

Security

–Unauthorized Access

–Viruses

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NETWORK APPLICATIONS

Marketing andSales

FinancialServices

Manufacturing

ElectronicMessaging

Teleconferencing

CableTelevision

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PROTOCOLS

“Set of Rules Governing

Communication”

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PROTOCOLS

Protocols defines:

–What is Communicated?

–How, it is Communicated?

–When, it is Communicated?

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PROTOCOLS

Elements of a Protocol:

–Syntax

–Semantics

–Timing

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PROTOCOL

ARCHITECTURE

“Instead of having a single Module

for performing communication, there is a

structured set of modules that implement

communications function”

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Simplified File Transfer

Architecture

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SUGGESTED READING

Section 1.2, “Data Communications and Networking” 4th Edition by Behrouz A. Forouzan

Sections 1.1, 1.2, “Data and ComputerCommunication” 6th Edition by WilliamStallings

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SUGGESTED READING

Section 1.3, “Data Communications and Networking” 4th Edition by Behrouz A. Forouzan

Sections 1.3, “Data and Computer Communication” 6th Edition by William Stallings

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SUGGESTED READING

Section 1.4 “Data Communications andEdition by Behrouz A.Networking” 4th

Forouzan

Sections 1.1,2.1 “Data and Computer Communication” 6th Edition by William Stallings

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QUESTIONS/COMMENTS?

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