Data Communication CSNS 241 Lecture 01 PDF

GHANA COMMUNICATION TECHNOLOGY UNIVERSITY FACULTY OF COMPUTING AND INFORMATION SYSTEMS DEPARTMENT OF INFORMATION TECHNOLOGY DATA COMMUNICATION CSNS 241 Course Instructor DR FELIX L. ARYEH, CC PhD, MSc, BSc, MISC2...

GHANA COMMUNICATION TECHNOLOGY UNIVERSITY FACULTY OF COMPUTING AND INFORMATION SYSTEMS DEPARTMENT OF INFORMATION TECHNOLOGY DATA COMMUNICATION CSNS 241 Course Instructor DR FELIX L. ARYEH, CC PhD, MSc, BSc, MISC2, MIEEE, MIAENG, MIET-GH, MGARNET  INTRODUCTION ❑Outline Data Communications ❑Who I am ❑Course Information and Outline of CSNS 241 ❑Expected Learning Outcomes ❑Rules ❑All Chapters Dr Felix L. Aryeh, CC 2  INTRODUCTION ❑About me ❑Name: Dr Felix L. Aryeh, CC Data Communications ❑Position: Senior Lecturer @ UMaT ❑Membership: MISC2, MIEEE, MIAENG, MIET-GH, MGARNET ❑Email: [email protected] ❑Research Areas: ❑ Wireless and Wired Network Security | Web Applications and Dr Felix L. Aryeh, CC Internet Technologies | Cyber Security | Opensource Web Applications | Opensource Firewall Systems | Computer Graphics | Artificial Intelligence | Machine Learning 3  Course Presentation ❑The course will be presented through a Data Communications combination of: ❑Weekly Lectures (i.e., face-to-face lectures/VLE); ❑Tutorials; ❑Student Led Presentations; and ❑Take Home Assignments Dr Felix L. Aryeh, CC 4  Course Objectives ❑The objectives for this course are as follows: Data Communications ❑ For students to understand the scientific principles and concepts behind the design and organization of network systems; ❑ For students to obtain hands-on experience in designing and management of a computer network system; ❑ To introduce students to the fundamental types of computer networks; Dr Felix L. Aryeh, CC ❑ To demonstrate the TCP/IP & OSI model merits & demerits; and 5 ❑ To know the role of various protocols in networking  RECOMMENDED TEXTBOOKS & REFERENCES ❑ The following textbooks have been recommended to ensure that students gain a deeper understanding of the course: Data Communications ❑ Ramon Nastase, “Computer Networking For Beginners”, amazon digital services llc - kdp print us, 2018 ❑ Douglas Comer, “Computer Networks And Internets”, 5th edition, prentice hall, 2009. ❑ Russ White and Ethan banks,” Computer Networking Problems And Solutions: An Innovative Approach To Building Resilient, Modern Networks”, 1st edition, Addison wesley professional. ❑ Michael B. White, “Computer Networking: The Complete Guide To Understanding Wireless Technology, Network Security, Computer Architecture And Communications Systems (Including Cisco, CCNA And CCENT)”, create space independent publishing platform, 2018. Dr Felix L. Aryeh, CC ❑ Olivier Bonaventure, “Computer Networking: Principles, Protocols, And Practice”, the saylor foundation, release 0.25, 2011. 6  INTRODUCTION ❑Course Information (CSNS 241) Data Communications ❑Lecture hours: 2 ❑Continuous Assessment: 40% ❑Attendance: 5 - 10% ❑Quizzes - 2 or 3 (Online) ❑Pop Quizzes for Attendance - Minimum of 5 ❑Group Project or Assignment - 1 Dr Felix L. Aryeh, CC ❑Individual Presentation – Practical (In Person) 7 ❑End of Semester: 50%  LECTURE ONE DATA COMMUNICATION AND NETWORKING CONCEPTS Data Communications ❑ Student learning outcomes ❑ After going through this lecture, students should be able to: ❑ Describe what data communication system is; ❑ Understand the elements that make up a data communication system; ❑ Understand the factors that affect data communication; Dr Felix L. Aryeh, CC and ❑ Describe the characteristics of network architectures: 8 reliability, performance and security.  COMMUNICATION ❑ Definition of Communication ❑ The act of sharing information between individuals Data Communications ❑ Types of Communication ❑ Local Communication: ❑ Occurs face-to-face ❑ Involves direct interaction without the need for technological mediums ❑ Remote Communication: ❑ Takes place over distance, facilitated by technology ❑ Telecommunication: Dr Felix L. Aryeh, CC ❑ Derived from Greek "tele," meaning "far" ❑ Includes methods like telephony, telegraphy, and television ❑ Data Communication 9 ❑ Exchange of data between two devices over a transmission medium (e.g., wire cable or wireless)  COMMUNICATION ❑ Requirements for Data Communication ❑ Communicating devices must be part of a communication system Data Communications ❑ System includes: ❑ Hardware: Physical equipment ❑ Software: Programs and protocols ❑ Key Techniques in Data Communication ❑ Modulation: Encoding digital data onto an analog carrier signal ❑ Encoding: Converting digital data into a specific code or format ❑ Multiplexing: Combining multiple data streams into a single transmission channel Dr Felix L. Aryeh, CC ❑ Applications of Data Communication ❑ Used in the internet, telecommunications, computer networks, and wireless systems 10 ❑ Essential for modern information exchange and digital communication  DATA COMMUNICATION ❑ Definition ❑ Exchange of data or information between devices over a communication Data Communications channel ❑ Channels can be wired or wireless, from simple cables to complex networks ❑ Forms of Data Communication ❑ Text, voice, video, and other types of digital data ❑ Process of Communication ❑ Encoding: Sender encodes the data ❑ Transmission: Data travels through the channel ❑ Decoding: Receiver decodes the data ❑ Importance in Modern Systems Dr Felix L. Aryeh, CC ❑ Essential for internet, telecommunication networks, and computer networks ❑ Enables efficient and reliable information exchange ❑ Supports communication and collaboration across individuals, organizations, 11 and machines  DATA COMMUNICATION ❑ Key Characteristics of an Effective Data Communication System ❑ Delivery Data Communications ❑ Data must reach the correct destination ❑ Only intended device or user should receive the data ❑ Accuracy ❑ Data must remain unaltered during transmission ❑ Uncorrected errors make data unusable ❑ Timeliness ❑ Data should be delivered promptly ❑ Real-time transmission required for audio and video (delivered in order and without Dr Felix L. Aryeh, CC delay) ❑ Jitter ❑ Variation in packet arrival times, causing uneven delay 12 ❑ Example: inconsistent delays in video packets result in poor video quality  Factors Affecting Quality of Data Communication ❑Quality of Data Communication Data Communications ❑ Defined by accuracy, reliability, and efficiency of data transmission ❑Factors Influencing Quality ❑ Bandwidth ❑ Amount of data that can be transmitted over time ❑ Higher bandwidth enables faster and efficient communication Dr Felix L. Aryeh, CC ❑ Latency ❑ Time delay between data transmission and receipt 13 ❑ High latency causes slow and unreliable communication  Factors Affecting Quality of Data Communication ❑Factors Influencing Quality Data Communications ❑Error Rate ❑ Frequency of errors during transmission ❑ High error rates lead to data corruption and loss ❑Signal-to-Noise Ratio ❑ Comparison of signal strength to background noise ❑ Higher ratio ensures clearer and more reliable communication Dr Felix L. Aryeh, CC ❑Interference ❑ Disruption from other signals or devices 14 ❑ Can result in data loss or corruption  Classification of Factors Affecting DataCom Quality ❑ Internal Factors ❑ Related to the nature of the message itself Data Communications ❑ Examples: ❑ Message size ❑ Message complexity ❑ Message importance ❑ External Factors ❑ Related to network complexity and device traffic ❑ Examples: Dr Felix L. Aryeh, CC ❑ Quality of the pathway between sender and recipient ❑ Number of concurrent messages on the network 15 ❑ Time allocated for successful communication  Components of a Data Communication System ❑ Definition ❑ Complex arrangement of hardware, software, protocols, and procedures for Data Communications data transmission ❑ Key Components ❑ Message ❑ The information or data to be communicated (e.g., text, numbers, pictures, audio, video) ❑ Sender ❑ Device that initiates the data message (e.g., computer, telephone, video camera) ❑ Receiver ❑ Device that receives the message (e.g., computer, television, workstation) ❑ Transmission Medium Dr Felix L. Aryeh, CC ❑ Physical path for message travel from sender to receiver (e.g., cables, wireless) ❑ Protocol ❑ Set of rules governing data communication 16 ❑ Ensures devices can understand each other Data Communications Dr Felix L. Aryeh, CC Components of a Data Communication System 17  DataCom Protocol Functions ❑ Data Sequencing ❑ Precedence and Order of Transmission ❑ Divides long messages into smaller ❑ Allocates network resources to nodes based Data Communications packets with numbering to detect on priority loss/duplication ❑ Connection Establishment and ❑ Data Routing Termination ❑ Defines the most efficient path from ❑ Manages connection setup, maintenance, source to destination and termination between nodes ❑ Data Formatting ❑ Data Security ❑ Specifies structure within packets (e.g., ❑ Protects data from unauthorized access and data, control, addressing info) ensures privacy ❑ Flow Control ❑ Log Information ❑ Regulates data flow to prevent fast ❑ Records network activities for usage Dr Felix L. Aryeh, CC senders from overwhelming slow tracking and billing purposes receivers ❑ Error Control ❑ Detects errors and retransmits faulty 18 data blocks to ensure accuracy  Components of a Data Communication System ❑ A typical data communication system is shown in Figure 1.1 Data Communications Dr Felix L. Aryeh, CC Figure 1.1: Element of Data Communication System 19  DATA FLOW IN A NETWORK ❑Definition Data Communications ❑ Movement of data from one device to another over a network ❑Types of Data Flow ❑ Simplex ❑ Half-Duplex ❑ Full-Duplex (Duplex) Dr Felix L. Aryeh, CC 20  DATA FLOW IN A NETWORK ❑ Definition Data Communications ❑ Data transmission in one direction only ❑ One party acts as transmitter, the other as receiver ❑ Characteristics ❑ Unidirectional, like a one-way street ❑ Utilizes the full channel capacity for data transmission in a single direction ❑ Example ❑ Simple radio: Receives data from stations but cannot transmit data back Dr Felix L. Aryeh, CC 21 Figure 1.4 Simplx Data Flow Structure  DATA FLOW IN A NETWORK ❑ Definition Data Communications ❑ Data can flow in both directions, but only one direction at a time ❑ Characteristics ❑ Devices can either transmit or receive, not both simultaneously ❑ If both devices attempt to transmit simultaneously, a collision occurs, causing data loss ❑ Example ❑ Device A sends data to Device B while Device B is in receive mode, and vice versa Dr Felix L. Aryeh, CC 22 Fig. 1.5 Half-Duplex Data Flow Structure  DATA FLOW IN A NETWORK ❑ Definition ❑ Allows simultaneous data transmission in both directions Data Communications ❑ Characteristics ❑ Operates like a two-way street with bi-directional traffic ❑ Many modems support both full-duplex and half-duplex modes, chosen based on communication program requirements ❑ Transmitted data is validated as it is echoed back, ensuring accuracy ❑ Example ❑ Telephone communication: Both parties can talk and listen simultaneously Dr Felix L. Aryeh, CC 23 Fig. 1.6 Full-Duplex Data Flow Structure  DATA REPRESENTATION TECHNIQUES ❑ Text ❑ Represented as a bit pattern (sequence of 0s and 1s) Data Communications ❑ Numbers ❑ Represented by direct binary conversion for simplicity in mathematical operations ❑ Images ❑ Composed of a matrix of pixels (picture elements) in bit patterns ❑ Audio ❑ Continuous form representing sound or music, different from discrete forms like text and images Dr Felix L. Aryeh, CC ❑ Video ❑ Can be continuous (e.g., from a TV camera) or a sequence of 24 images arranged to convey motion  NETWORK COMPONENTS ❑ Definition Data Communications ❑ Hardware and software elements enabling communication and data transfer in a network ❑ Categories of Devices ❑ Message-Originating Devices ❑ Initiate communication ❑ Examples: computers, laptops, servers ❑ Message-Directing and Managing Devices Dr Felix L. Aryeh, CC ❑ Direct and manage network traffic ❑ Examples: routers, switches, repeaters 25  NETWORK INTERFACE CARDS ❑ Definition ❑ Hardware component (also called network adapter) connecting a computer to a Data Communications network ❑ Enables data packet transmission and reception for network communication ❑ Types of NICs ❑ Ethernet NIC: Wired connections; speeds include 10 Mbps, 100 Mbps, and 1 Gbps ❑ Wi-Fi NIC: Wireless connections; standards include 802.11n, 802.11ac, and 802.11ax ❑ Bluetooth NIC: For Bluetooth network connections ❑ MAC Address ❑ Unique 48-bit identifier assigned by the manufacturer ❑ Written in hexadecimal format; used for identifying NIC on the network Dr Felix L. Aryeh, CC ❑ Configuration ❑ Software-configurable settings: IP address, subnet mask, default gateway 26 ❑ Enables network communication with other devices  NETWORK INTERFACE CARDS ❑ Figure 1.2 shows an image of different types of NICs which can be used in computer systems. Data Communications Dr Felix L. Aryeh, CC Figure. 1.2 Different Types of Network Interface Cards 27  NETWORK DEVICES ❑ Definition ❑ Hardware components enabling Data Communications communication, data transmission, and management across networks ❑ Facilitate fast, secure, and accurate data transfer within (intra-network) or across (inter-network) networks ❑ Examples of Network Devices ❑ Repeater ❑ Extends network reach by regenerating and amplifying signals Dr Felix L. Aryeh, CC ❑ Receives a weak signal, retransmits it with higher power to maintain network integrity ❑ Operates at the Physical layer of the OSI model ❑ Applicable for both wired and wireless networks 28 Figure. 1.3 A 2-port Repeater Device  NETWORK DEVICES CONT’D ❑ Definition ❑ Connects multiple wires from different branches (e.g., Data Communications star topology) ❑ Broadcasts data packets to all connected devices without filtering ❑ Lacks intelligence for optimal data path selection, causing inefficiencies ❑ Types of Hubs ❑ Active Hub ❑ Equipped with its own power supply ❑ Cleans, boosts, and relays signals, functioning as both repeater and wiring center Dr Felix L. Aryeh, CC ❑ Extends maximum distance between nodes Figure. 1.4 Port Hub ❑ Passive Hub ❑ Relies on the active hub for power supply 29 ❑ Relays signals without boosting or cleaning ❑ Cannot extend the distance between nodes  NETWORK DEVICES CONT’D ❑ Definition ❑ Connects multiple devices within a network, Data Communications enabling direct communication ❑ Operates at the Data Link Layer (Layer 2) of the OSI model ❑ Functionality ❑ Forwards data packets to intended recipients only, reducing congestion ❑ Commonly used in LANs to connect devices like computers, printers, and servers ❑ Provides fast, efficient communication ❑ Benefits of Switches Dr Felix L. Aryeh, CC ❑ Reduces network congestion and improves performance ❑ Can segment a network into smaller 30 subnetworks (improves security and manageability) Figure. 1.5 Switch  NETWORK DEVICES CONT’D ❑ Definition ❑ Connects two or more network segments, Data Communications enabling communication between them ❑ Operates at the Data Link Layer (Layer 2) of the OSI model ❑ Functionality ❑ Forwards data packets between network segments ❑ Commonly used in LANs to link different parts of a network ❑ Benefits of Bridges ❑ Reduces network congestion by dividing Dr Felix L. Aryeh, CC networks into smaller segments ❑ Enhances network speed and efficiency ❑ Can be used to segment networks for Figure. 1.6 A 4-Port Bridge 31 improved security (limits inter-segment traffic)  NETWORK DEVICES CONT’D ❑ Definition ❑ Connects two or more distinct networks, enabling Data Communications inter-network communication ❑ Operates at the Application Layer (Layer 7) of the OSI model ❑ Functionality ❑ Translates protocols and addressing schemes between networks with different technologies ❑ Supports communication between networks with varying communication protocols, data formats, or architectures ❑ Benefits of Gateways Dr Felix L. Aryeh, CC ❑ Acts as a bridge between different network technologies ❑ Facilitates secure communication across networks with different security policies Figure. 1.7 A Gateway 32 ❑ Commonly used to connect different parts of an organization or multiple organizations  NETWORK DEVICES CONT’D ❑ Definition ❑ Connects multiple networks, allowing inter-network Data Communications communication ❑ Operates at the Network Layer (Layer 3) of the OSI model ❑ Functionality ❑ Forwards data packets between networks using IP addresses ❑ Commonly used in WANs and the internet to connect diverse networks ❑ Benefits of Routers ❑ Provides scalable connections across networks of various sizes and technologies ❑ Can segment a network into smaller subnetworks to improve security and manageability Dr Felix L. Aryeh, CC ❑ Additional Capabilities ❑ Traffic filtering based on specific criteria ❑ Network Address Translation (NAT) 33 ❑ Virtual Private Network (VPN) connectivity Figure. 1.7 A Router  Lecture Questions 1. Differentiate between data & information. Data Communications 2. What are the different forms in which data can be represented? 3. What are the characteristics of data communication? 4. What are the components of a data communication system? 5. What is meant by quality of communication? 6. Outline some internal and external factors that impact the quality of communication. 7. What is a network device Dr Felix L. Aryeh, CC 8. Briefly describe some network devices 9. What is a network interface card 34 10. What are network components  Dr Felix L. Aryeh, CC Data Communications 35 LECTURE TWO SIGNALS AND BANDWIDTH THANK YOU VERY MUCH