Transcript Categories of Networks

Data Communication &
Networking DKT 224
McGraw-Hill
Ir Anuar Mat Safar
04-9851684 / 013-4223242
Puan Shahadah Bt. Ahmad
04-9854979 / 017-5722339
School of Computer & Communication
Engineering KUKUM
[email protected]
[email protected] ©The McGraw-Hill Companies, 1Inc., 2000
Course Outcomes
1.
2.
3.
4.
Students will be able to understand the theory and
basic of data communication and network.
Able to identify network connection concept and
protocol used
Students be familiarize with the data communication
network equipments and instruments to analyze
network protocol and perform some troubleshooting
Students be exposed to network architecture and new
technologies in data communication and network.
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Syllabus
Study
Course Content
W
e
e
k
1,2
INTRODUCTION
Chapter 1
Introduction to data communications
component, data representation and data flow
Chapter 2
Introduction to data communication networks ,
-network criteria, physical structures, network models, categories of
networks and Internet work.
-protocols and standards
(4 hours)
3,4,
5
PHYSICAL LAYER AND MEDIA (review)
Chapter 3,4,5
Data and signals, Digital transmission and analog transmission
Chapter 6 ,7
3
Syllabus
Study Week
6,7
Course Content
DATA LINK LAYER
Chapter 10
Error Detection and Correction
(4 hours)
9,10
DATA LINK LAYER( cont..)
Chapter 11,12
Data link control & Multiple access
(4 hours)
4
Syllabus
Study Week
Course Content
11,12
Chapter 13,14
Wired and wireless LANs
(4 hours)
13,14
SECURITY
Chapter 30,31
Cryptography & network Security
(4 hours)
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Assessment
Final Exam - 50 %
Course Work – 50 %
Lab – 30 %
Test/ Assigment – 10%
Lab Project – 10%

McGraw-Hill
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©The McGraw-Hill Companies, Inc., 2000
Lab experiment
LAB 1 - Introduction to LINUX
LAB 2 - Network protocol analyzer
LAB 3 - Network setup 1
LAB 4 - Network setup 2
LAB 5 - Wireless access point
configuration
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References
1.Behrouz A. Forouzan, Data Communications and
Networking, 4th Edition, McGraw Hill, 2007
(TEXT BOOK)
2. William Stalling, Data and Computer
Communications ,7th Edition, Prentice Hall,
2005.
3.Wayne Tomasi, Introduction to Data
Communications and Networking,
McGraw-Hill
Prentice Hall,2004.
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©The McGraw-Hill Companies, Inc., 2000
Chapter 1
Introduction
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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1-1 DATA COMMUNICATIONS
The term telecommunication means communication at a
distance. The word data refers to information presented
in whatever form is agreed upon by the parties creating
and using the data. Data communications are the
exchange of data between two devices via some form of
transmission medium such as a wire cable.
Topics discussed in this section:
Components
Data Representation
Data Flow
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Figure 1.1 Five components of data communication
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Data Representation
TEXT – unicode (32 bits to represent
character)- ASCII
NUMBERS
IMAGES-composed of a matrix of pixel
AUDIO- recording or broadcasting of
sound or music.
VIDEO- recording or broadcasting of a
picture or movie
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Figure 1.2 Data flow (simplex, half-duplex, and full-duplex)
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1-2 NETWORKS
A network is a set of devices (often referred to as nodes)
connected by communication links. A node can be a
computer, printer, or any other device capable of sending
and/or receiving data generated by other nodes on the
network.
Topics discussed in this section:
Distributed Processing
Network Criteria
Physical Structures
Network Models
Categories of Networks
Interconnection of Networks: Internetwork
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NETWORKS
Set of nodes connected via physical links
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1) Distributing Processing
2) Sharing Data and centralization
3) Security and robustness
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Network Criteria
1) Performance, Transmission and
response times’ throughput and delay.
2) Reliability: How often the networks fail
3) Security: Privacy and integrity of
communication Data; recovery from
breaches and data loss.
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Physical Structures:
Types of connections:
1) Point to Point: (P to P) Dedicated link to
be utilized only by end devices.
2) Multipoint (Multidrop): Many end
devices share the link capacity.
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Figure 1.3 Types of connections: point-to-point and multipoint
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Physical Topology
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Figure 1.4 Categories of topology
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Physical Topology
A) Mesh:
Each device has dedicated point-to-point
link to other devices. Fully connected
mesh will have n( n-1)/ 2 F.D. links

Where n = number of nodes
Pros: Fast communication, Robust and
Privacy (Security)
Cons: Cabling Space and cost
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Figure 1.5 A fully connected mesh topology (five devices)
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Physical Topology (cont..)
B) Star:
Devices are connected Point to Point to a
central “Hub” (Controller Exchanger)
Pros: Less cabling and H/W ports, two
hops only.
Cons: Not robust
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Figure 1.6 A star topology connecting four stations
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Figure 1.7 A bus topology connecting three stations
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
C) Bus:
Multipoint link as “backbone” for a network
where devices have drop line to tap into
the bus
Pros: Less Cabling
Cons: Topology dependent, limit number
of nodes on the bus due to signal power
loss with distance, not so robust
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Figure 1.8 A ring topology connecting six stations
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C) Ring: Each device connects Point to
Point with only two other devices in a left
and right neighbors arrangement via a
repeater.
Pros : easy installation, better fault
isolation and robustness.
Cons: N/2 hops communication
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Figure 1.9 A hybrid topology: a star backbone with three bus networks
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D) Hybrid: • Pizza “star” inside a “ ring”
Pros: Better robustness, still low cost,
Delay is 1 hop (until the star is not with a
ring cut, max 2. • Star of busses
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Categories of Networks:
Local Area Networks (LAN): Few
Kilometers Connects devices (Pcs,
printers, servers.) within the same room,
building, company, and campus.
Topologies most used are bus, ring and
star.
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Figure 1.10 An isolated LAN connecting 12 computers to a hub in a closet
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Categories of Networks(cont..)
Wide Area Networks (WAN):
span a large geographical area about
100’s – 1000’s of Km
1) Switched: End users connected via a
cloud of switches (subnet).
2) Point-to Point: Line leased from
telephone company/ TV connecting users
to the ISP for Internet access.
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alternative technologies used include:
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circuit switching
packet switching
frame relay
Asynchronous Transfer Mode (ATM
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Circuit Switching
uses a dedicated communications path
established for duration of conversation
comprising a sequence of physical links
with a dedicated logical channel
eg. telephone network
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Packet Switching
data sent out of sequence
small chunks (packets) of data at a time
packets passed from node to node
between source and destination
used for terminal to computer and
computer to computer communications
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Frame Relay
packet switching systems have large
overheads to compensate for errors
modern systems are more reliable
errors can be caught in end system
Frame Relay provides higher speeds
with most error control overhead removed
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Asynchronous Transfer Mode
(ATM)
evolution of frame relay
fixed packet (called cell) length
with little overhead for error control
anything from 10Mbps to Gbps
constant data rate using packet switching
technique with multiple virtual circuits
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Figure 1.11 WANs: a switched WAN and a point-to-point WAN
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Figure 1.12 A heterogeneous network made of four WANs and two LANs
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Categories of Networks(cont..)
Metropolitan Area Networks:
MAN town/city
High-speed backbone linking multiple
LAN’s, DSL, TV cables.
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1-3 THE INTERNET
The Internet has revolutionized many aspects of our daily
lives. It has affected the way we do business as well as the
way we spend our leisure time. The Internet is a
communication system that has brought a wealth of
information to our fingertips and organized it for our use.
Topics discussed in this section:
A Brief History
The Internet Today (ISPs)
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The Internet
Internet evolved from ARPANET
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first operational packet network
applied to tactical radio & satellite nets also
had a need for interoperability
led to standardized TCP/IP protocols
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The Internet:
Huge number of interconnected Networks
(100000’s) private organized, e.g.’ government,
schools, research facilities, in many countries
Collection of LAN’S, MAN’S and WAN’s.
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􀂄 The internet protocol stack is the TCP/IP
􀂄 End users use the internet via Internet Service
providers (ISPs) which are of the following
hierarchies:
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Figure 1.13 Hierarchical organization of the Internet
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Internet Elements
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Internet Architecture
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Example Configuration
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1-4 PROTOCOLS AND STANDARDS
In this section, we define two widely used terms: protocols
and standards. First, we define protocol, which is
synonymous with rule. Then we discuss standards, which
are agreed-upon rules.
Topics discussed in this section:
Protocols
Standards
Standards Organizations
Internet Standards
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What is a protocol?
 Communications between computers
requires very specific unambiguous rules
 A protocol is a set of rules that governs
how two or more communicating parties
are to interact
Examples
Internet Protocol (IP)
Transmission Control Protocol (TCP)
HyperText Transfer Protocol (HTTP)
Simple Mail Transfer Protocol (SMTP)
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Elements:
1) Syntax: PDU format
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2) Semantics: The meaning of each PDU’s field
3) Timing: Synchronization of communication
when PDU is to be transferred and its data rate.
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What is a standard?
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• A “ standard is set of guidelines” to users
and manufactures to ensure interconnectivity.
1) “Defacto” not approved but widely used
(TCP/IP)
2) “Dejure”: approved by recognized body
(IEEE 802.X).
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Summary
introduced data communications needs
communications model
defined data communications
overview of networks
introduce Internet
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