Data Communication Networking DKT 224 Mc Graw-Hill

Data Communication & Networking DKT 224 Mc. Graw-Hill Ir Anuar Mat Safar 04 -9851684 / 013 -4223242 Puan Shahadah Bt. Ahmad 04 -9854979 / 017 -5722339 School of Computer & Communication Engineering KUKUM anuarms@unimap. edu. my 1 shahadah@unimap. edu. my ©The Mc. Graw-Hill Companies, Inc. , 2000

Course Outcomes 1. 2. 3. 4. Students will be able to understand 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. 2

Syllabus Course Content Study 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, PHYSICAL LAYER AND MEDIA (review) 5 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 11, 12 Course Content Chapter 13, 14 Wired and wireless LANs (4 hours) 13, 14 SECURITY Chapter 30, 31 Cryptography & network Security (4 hours) 5

Assessment l. Final Exam - 50 % l. Course Work – 50 % Lab – 30 % n. Test/ Assigment – 10% n. Lab Project – 10% n Mc. Graw-Hill 6 ©The Mc. Graw-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 7

References 1. Behrouz A. Forouzan, Data Communications and Networking, 4 th Edition, Mc. Graw Hill, 2007 (TEXT BOOK) 2. William Stalling, Data and Computer Communications , 7 th Edition, Prentice Hall, 2005. 3. Wayne Tomasi, Introduction to Data Communications and Networking, Prentice Hall, 2004. Mc. Graw-Hill 8 ©The Mc. Graw-Hill Companies, Inc. , 2000

Chapter 1 Introduction Copyright © The Mc. Graw-Hill Companies, Inc. Permission required for reproduction or display. 9

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 10

Figure 1. 1 Five components of data communication 11

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 12

Figure 1. 2 Data flow (simplex, half-duplex, and full-duplex) 13

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 14

NETWORKS Set of nodes connected via physical links n n n 1) Distributing Processing 2) Sharing Data and centralization 3) Security and robustness 15

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. 16

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. 17

Figure 1. 3 Types of connections: point-to-point and multipoint 18

Physical Topology 19

Figure 1. 4 Categories of topology 20

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 n Where n = number of nodes Pros: Fast communication, Robust and Privacy (Security) Cons: Cabling Space and cost 21

Figure 1. 5 A fully connected mesh topology (five devices) 22

Physical Topology (cont. . ) B) Star: Devices are connected Point to a central “Hub” (Controller Exchanger) Pros: Less cabling and H/W ports, two hops only. Cons: Not robust 23

Figure 1. 6 A star topology connecting four stations 24

Figure 1. 7 A bus topology connecting three stations 25

n 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 26

Figure 1. 8 A ring topology connecting six stations 27

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 28

Figure 1. 9 A hybrid topology: a star backbone with three bus networks 29

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 30

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. 31

Figure 1. 10 An isolated LAN connecting 12 computers to a hub in a closet 32

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. 33

alternative technologies used include: n n circuit switching packet switching frame relay Asynchronous Transfer Mode (ATM 34

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 35

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 36

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 37

Asynchronous Transfer Mode (ATM) evolution of frame relay fixed packet (called cell) length with little overhead for error control anything from 10 Mbps to Gbps constant data rate using packet switching technique with multiple virtual circuits 38

Figure 1. 11 WANs: a switched WAN and a point-to-point WAN 39

Figure 1. 12 A heterogeneous network made of four WANs and two LANs 40

Categories of Networks(cont. . ) Metropolitan Area Networks: MAN town/city High-speed backbone linking multiple LAN’s, DSL, TV cables. 41

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) 42

The Internet evolved from ARPANET n n first operational packet network applied to tactical radio & satellite nets also had a need for interoperability led to standardized TCP/IP protocols 43

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. n n internet protocol stack is the TCP/IP The users use the internet via Internet Service End providers (ISPs) which are of the following hierarchies: 44

Figure 1. 13 Hierarchical organization of the Internet 45

Internet Elements 46

Internet Architecture 47

Example Configuration 48

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 Organizations Internet Standards 49

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) §Hyper. Text Transfer Protocol (HTTP) §Simple Mail Transfer Protocol (SMTP) 50

Elements: 1) Syntax: PDU format n n 2) Semantics: The meaning of each PDU’s field 3) Timing: Synchronization of communication when PDU is to be transferred and its data rate. 51

What is a standard? n n n • 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). 52

Summary introduced data communications needs communications model defined data communications overview of networks introduce Internet 53