Data Communication and Computer Networks Introduction

Instructor: Dr. Waqas Ahmed.
Marks Distribution: Quiz ( $7.5\%$ ), Assignment ( $7.5\%$ ), Mid-Term ( $22.5\%$ ), Final ( $37.5\%$ ), and Lab ( $25\%$ ).
Requirement: Every student must pass the Cisco CCNA_Introduction to Networks course via netacad.
Primary Textbooks: * Data Communications & Networking by A.B. Forouzan (5th Edition). * Data and Computer Communications by William Stallings (10th Edition). * Computer Networking: A Top-Down Approach by Kurose, Rose (5th Edition).

Definition: The exchange of data between two devices via a transmission medium.
Five Components: Message, Sender, Receiver, Medium, and Protocol.
Data Flow Modes: * Simplex: One-way communication (e.g., Mainframe to Monitor). * Half-duplex: Two-way communication but only one station transmits at a time. * Full-duplex: Simultaneous two-way communication.

Nodes: Devices such as computers or printers connected by communication links.
Host Roles: * Servers: Provide information (Email, Web, File servers). * Clients: Request information from servers.
Peer-to-Peer (P2P): Devices act as both clients and servers; ideal only for small, simple networks.
Intermediary Devices: Switches, wireless access points, routers, and firewalls that manage data flow and path information.
Media Types: * Metal wires: Electrical impulses. * Fiber-optic: Pulses of light. * Wireless: Electromagnetic waves.

Topology Types: * Mesh: Fully connected; high redundancy. * Star: Devices connect to a central hub. * Bus: Devices connect to a common cable with taps. * Ring: Circular connection with repeaters.
Topology Diagrams: * Physical: Shows actual hardware locations and cable installation. * Logical: Shows ports, addressing schemes, and data paths.
Network Scale: * LAN (Local Area Network): Spans a small area; internally administered. * WAN (Wide Area Network): Spans wide geographic areas; managed by service providers. * The Internet: A worldwide collection of interconnected LANs and WANs.

Fault Tolerance: Uses packet switching and redundant paths to minimize failure impact.
Scalability: Ability to expand for new users without performance degradation.
Quality of Service (QoS): Manages bandwidth to ensure reliable delivery for time-sensitive data like voice and video.
Network Security Goals: * Confidentiality: Intended recipients only. * Integrity: Data remains unaltered during transmission. * Availability: Reliable access for authorized users.

Home/SOHO Connections: Cable, DSL, Cellular, Satellite, and Dial-up.
Business Connections: Dedicated Leased Lines, Ethernet WAN, and Business DSL ( $SDSL$ ).
Converged Networks: Integration of data, voice, and video over a single network infrastructure.
Current Trends: * BYOD (Bring Your Own Device): Using personal devices for professional/educational tasks. * Cloud Computing: Public, Private, Hybrid, and Custom clouds managed through data centers. * Powerline Networking: Data transmission over existing electrical wiring.