Data Communication & Network
REFERENCES
1
REFERENCES
1. Behrouz Forouzan, Data Communications and Network, 4th Edition, McGraw-Hill, 2007. (TEXT BOOK) 2. Andrew S Tanenbaum, Computer Networks, Prentice Hall, 1997. 3. E. Ramos, A. Schoroeder and A. Beheler, Beheler, Computer Network Concepts, McMillan, 1996. 4. Azhar, Azhar, Haniza and Zakiah, Zakiah, Komunikasi Komunikasi Data and and network(Modul network(Modul Pengajaran), Pengajaran), Edisi Pertama, Pertama, 2005. 5. B. Nazrulazhar and H. Erman, Data Communications Communications and Network Network : Practical Approach, 1st Edition, Venton, 2008.
Data Communication & Network
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ASSESSMENT Course work
Percentage
Assignment
15%
REFERENCES
1. Behrouz Forouzan, Data Communications and Network, 4th Edition, McGraw-Hill, 2007. (TEXT BOOK) 2. Andrew S Tanenbaum, Computer Networks, Prentice Hall, 1997. 3. E. Ramos, A. Schoroeder and A. Beheler, Beheler, Computer Network Concepts, McMillan, 1996. 4. Azhar, Azhar, Haniza and Zakiah, Zakiah, Komunikasi Komunikasi Data and and network(Modul network(Modul Pengajaran), Pengajaran), Edisi Pertama, Pertama, 2005. 5. B. Nazrulazhar and H. Erman, Data Communications Communications and Network Network : Practical Approach, 1st Edition, Venton, 2008.
Data Communication & Network
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ASSESSMENT Course work
Percentage
Assignment
15%
ASSESSMENT Course work
Percentage
Assignment
15%
Laboratory tests
10%
Mid-term exam
15%
Quiz
15%
Presentation Presentation - Project
15%
Total Coursework
70%
Final Exam
30%
Total
100% Data Communication & Network
Course Outcomes Upon completion this course, students will be able to perform tasks
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Course Outcomes Upon completion this course, students will be able to perform tasks related to he following:
i. Explain the fundamental of data communication and networking concepts ii. Selecting the type of media, network topology and appropriate network technology with the latest technology. iii. Configure and troubleshoot basic network using guided and unguided media
Data Communication & Network
Data Communication and Network BIT1313
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Data Communication and Network BIT1313 Introduction
Data Communication & Network
Data Communication •
Data
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Data Communication •
Data •
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Data communication • •
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Information presented in whatever form is agreed upon by the parties creating and using the data Exchange of data between two devices Via some form of transmission medium
Telecommunication: communication at a distance (‘tele’ in Greek=‘far”)
Data Communication & Network
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TEXT – Unicode (32 bits to represent character)- ASCII
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NUMBERS - represented by bit patterns
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IMAGES-composed of a matrix of pixel
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AUDIO- recording or broadcasting of sound or music
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VIDEO- recording or broadcasting of a picture or movie
Data Communication & Network
Transmission Media
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Transmission Media
Data Communication & Network
Components of data communication
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Components of data communication
Data Communication & Network
Data flow (simplex, half-duplex, and full-duplex)
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Data flow (simplex, half-duplex, and full-duplex)
Data Communication & Network
Network Network: A set of devices (nodes) connected by communication links
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Network Network: A set of devices (nodes) connected by communication links Node: Computer, printer, or any device capable of sending and/or receiving data
Data Communication & Network
Network criteria
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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 crack and data loss.
Data Communication & Network
Type of Connection •
Point-to-point Dedicated link between two devices
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Type of Connection •
Point-to-point Dedicated link between two devices The entire capacity of the channel is reserved Ex) Microwave link, TV remote control
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Multipoint More than two devices share a single link Capacity of the channel is Spatially shared.
Data Communication & Network
Physical Topology
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Physical Topology
Data Communication & Network
Mesh Topology •
Each device has dedicated point-to-point link to other devices.
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Mesh Topology • •
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Each device has dedicated point-to-point link to other devices. Fully connected mesh will have n( n-1)/ 2 links Where n = number of nodes Advantages: Fast communication, Robust and Privacy (Security) Disadvantages: Cabling Space and cost
Data Communication & Network
Star Topology •
Dedicated point-to-point link only to a central controller, called a hub Hub acts as an exchange: No direct traffic between devices
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Star Topology •
Dedicated point-to-point link only to a central controller, called a hub
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Hub acts as an exchange: No direct traffic between devices
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Advantages: Less expensive, robust
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Disadvantages: dependency of the whole on one single point, the hub
Data Communication & Network
Bus Topology •
One long cable that links all nodes
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Bus Topology •
One long cable that links all nodes
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tap, drop line, cable end
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limit on the number of devices, distance between nodes
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Advantages: Easy installation, cheap
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Disadvantages: Difficult reconfiguration, no fault isolation, a fault or break in the bus stops all transmission
Data Communication & Network
Ring Topology •
Dedicated point-to-point link only with the two nodes on each sides
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Ring Topology •
Dedicated point-to-point link only with the two nodes on each sides
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One direction, repeater
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Advantages: Easy reconfiguration, fault isolation
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Disadvantage: Unidirectional traffic, a break in the ring cab disable the entire network
Data Communication & Network
Hybrid Topology Example: Main star topology with each branch connecting several
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Hybrid Topology
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Example: Main star topology with each branch connecting several stations in a bus topology To share the advantages from various topologies
Data Communication & Network
Categories of Networks
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Categories of Networks
Data Communication & Network
Local area network ( LAN) •
Usually privately owned
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Local area network ( LAN) •
Usually privately owned
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A network for a single office, building, or campus a few Km
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Common LAN topologies: bus, ring, star
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An isolated LAN connecting 12 computers to a hub in a closet
Data Communication & Network
Metropolitan area network (MAN) Designed to extend to an entire city
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Metropolitan area network (MAN)
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Designed to extend to an entire city
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Cable TV network, a company’s connected LANs
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Owned by a private or a public company
Data Communication & Network
Wide area network (WAN) •
Long distance transmission, e.g., a country, a continent, the world
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Enterprise network: A WAN that is owned and used by one company
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Wide area network (WAN) •
Long distance transmission, e.g., a country, a continent, the world
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Enterprise network: A WAN that is owned and used by one company
Data Communication & Network
Internetwork •
Internetwork (internet) : two or more networks are connected by internetworking devices
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Internetwork •
Internetwork (internet) : two or more networks are connected by internetworking devices
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Internetworking devices: router, router, gateway, gateway, etc.
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The Internet: a specific worldwide network
Data Communication & Network
Internetwork Intern etwork Examp Example le •
A heterogeneous network : four WANs and two LANs
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Internetwork Intern etwork Examp Example le •
A heterogeneous network : four WANs and two LANs
Data Communication & Network
The Int Intern ernet et •
The Internet has revolutionized many aspects of our daily lives. It has affected the way we do business as well
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The Int Intern ernet et •
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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 system that has brought a wealth of information to our fingertips and organized it for our use. 1967: ARPANET proposed by DoD’s ARPA(Advanced Research Project Agency)
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1969: ARPANET in a reality: UCLA, UCSB, SRI, U. of Utah
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1973: Vint Cerf and Bob Kahn propose TCP,
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To split TCP into two protocols TCP and IP
Data Communication & Network
Internet Today
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Internet Today
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ISP (Internet service providers) NISP (national ISP) NAP (network access point)
Data Communication & Network
Protocols
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Protocols
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Protocol : rule •
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A set of rules that govern data communication For communication to occur, entities must agree upon a protocol
Key elements of a protocol •
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Syntax: structure or format of data Semantics: meaning of each section in the structure Timing: when and how fast data should be sent
Data Communication & Network
Standards: agreed-upon rules •
Standards is essential in
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Standards: agreed-upon rules •
Standards is essential in •
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Creating/maintaining open and competitive markets Guaranteeing national/international interoperability
Two categories •
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De jure (“by law” or “by regulation’) standards De facto (“by fact ” or ‘by convention’) standards •
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Proprietary standards: closed standards Nonproprietary standards: open standards
Data Communication & Network
Standards Committees •
ISO
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Standards Committees •
ISO •
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ITU-T •
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Private non-profit corporation in the US
IEEE •
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Formerly, CCITT formed by UN
ANSI •
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Voluntary international organization
The largest engineering society in the world
EIA •
Non-profit organization in the US
Data Communication & Network
Internet Standards •
IETF (Internet Engineering Task Force)
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Internet Standards •
IETF (Internet Engineering Task Force)
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Internet Draft •
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working document with no official status with a 6-month lifetime
RFC (Request for Comment) •
Edited, assigned a number, and made available to all interested parties
Data Communication & Network
Summary
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Summary •
introduced data communications needs
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communications model
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defined data communications
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overview of networks
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introduce Internet
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Topics 1.
Layered Tasks
2.
The OSI Model
3.
Layers in the OSI Model
4.
TCP/IP Protocol Suite
5.
Addressing
Layered Model: Sending a Letter •
We use the concept of layers in our daily life. As an example, let us consider two friends who communicate through postal mail.
THE OSI MODEL •
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An International Standards Organization (ISO) standard that covers all aspects of network communications is the Open Systems Interconnection (OSI) model. It was first introduced in the late 1970s. An open system is a set of protocols that allows any two different systems to communicate regardless of their underlying architecture. purpose: show how to facilitate communication between different systems without requiring changes to the logic of the underlying hardware and software. The OSI model is not a protocol; it is a model for understanding and designing a network architecture that is flexible, robust, and interoperable. he OSI model was never fully implemented .
An Example Using the OSI Model
WCB/McGraw-Hill
The McGraw-Hill Companies, Inc., 1998
Physical Layer •
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The physical layer is responsible for movements of individual bits from one hop (node) to the next Mechanical and electrical specification, the procedures and functions
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Physical Layer: Duties •
Physical characteristics of interfaces and media
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Representation of bits
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Data rate
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Synchronization of bits
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Line configuration
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Physical topology
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Transmission mode
Data Link Layer •
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The data link layer is responsible for moving frames from one hop (node) to the next Transform the physical layer to a reliable (error-free) link
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Data Link Layer Example
WCB/McGraw-Hill
The McGraw-Hill Companies, Inc., 1998
Data Link Layer: Duties •
Framing
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Physical addressing
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Flow control
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Error control
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Access control
Hop-to-Hop Delivery
Network Layer •
The network layer is responsible for the delivery of packets from the source host to the destination host
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Network Layer: Duties •
Logical addressing and routing
Transport Layer •
The transport layer is responsible for delivery of a message from one process to another
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Transport Layer: Duties •
Service-point (port) addressing
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Segmentation and reassembly
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Connection control
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Flow control
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Error control
Reliable Process-to-Process Delivery of a Message
Session Layer •
Session layer is responsible for dialog control and synchronization
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Presentation Layer •
Presentation layer is responsible for translation, compression, and encryption
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Application Layer •
Application layer is responsible for providing services to the user
Data Communications Kwangwoon University
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Application Layer: Services
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Network virtual terminal
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Mail services
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File transfer, access, and management
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Directory services
Summary of Layers
TCP/IP and OSI Model
TCP/IP Protocol Suite •
Host-to-network : Physical and data link layer •
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Network layer •
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IP(Internet Protocl), ARP(Address Resolution Protocol), RARP(Reverse ARP), ICMP(Internet Control Message Protocol), IGMO(Internet Group Message Protocol)
Transport layer •
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No specific protocol
TCP(Transmission Control Protocol), UDP(User Datagram Protocl), SCTP(Stream Control Transmission Protocol),
Application Layer •
Combined session, presentation, and application layers
Addressing •
Four levels of addresses in TCP/IP protocols
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Physical (link), logical (IP, network), port, and specific addresses
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Relationship of Layers and Addresses
Data Communications Kwangwoon University
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Physical Address •
A node with physical address 10 sends a frame to a node with physical address 87. The two nodes are connected by a link (bus topology LAN). As the figure shows, the computer with physical address 10 is the sender, and the computer with physical address 87 is the receiver.
07:01:02:01:2C:4B A 6-byte (12 hexadecimal digits) physical address.
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Logical (IP) Address
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The physical addresses will change from hop to hop, but the logical addresses usually remain the same Data Communications Kwangwoon University
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Port Address •
The physical addresses change from hop to hop, but the logical and port addresses usually remain the same
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Specific Address •
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Some application have user-friendly addresses that are designed for that specific address Example 1: e-mail address:
[email protected] •
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Defines the recipient of an e-mail
Example 2: URL (Universal Resource Locator) : www.kbs.co.kr •
Used to find a document on the WWW
Data Communications Kwangwoon University
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