Computer Networks Course Overview

Course Objectives

• Understand fundamentals of computer networks, TCP/IP & OSI model.
• Analyze Data link layer Issues, Protocols.
• Explain Network layer Protocols, IP addressing.
• Identify end to end communication & various aspects in the Transport layer.
• Describe various user services in a network.

Course Structure

• Unit 1: Introduction to Networks
• Unit 2: Data Link Layer
• Unit 3: Network Layer
• Unit 4: Transport Layer
• Unit 5: Application Layer

Textbooks and References

1. Computer Networks - Andrew S Tanenbaum
2. Data Communications and Networking - Behrouz A. Forouzan

UNIT I: Introduction to Computer Networks

Data Communication Components

• Message: Information (text, numbers, audio, video).
• Sender: Device that sends data (computer, camera).
• Receiver: Device that receives data.
• Transmission Medium: Path for data (twisted-pair wire, radio waves).
• Protocol: Rules governing data communication.

Network Types and Topologies

• Types: LAN, MAN, WAN
• Topologies: Mesh, Star, Bus, Ring

Uses of Computer Networks

• Business Applications: Resource sharing, E-commerce.
• Home Applications: Remote access, Interactive entertainment.

Internet Overview

• Revolutionized communication and information access.
• History: ARPANET, TCP/IP development.

UNIT II: Data Link Layer

Design Issues

• Services: Provided to the network layer.
• Framing: Organizing data into frames.
• Error Control: Detection and correction.
• Flow Control: Preventing data overflow.

Error Detection Methods

• Parity Check: Ensures even/odd number of 1s.
• Cyclic Redundancy Check (CRC): Polynomial-based error detection.

Protocols

• Simplex Protocol: Unidirectional data transmission.
• Stop and Wait ARQ: Reliable data transmission with acknowledgments.

Multiple Access Protocols

• CSMA/CD: Carrier Sense Multiple Access with Collision Detection.
• CSMA/CA: Collision Avoidance mechanism.

UNIT III: Network Layer

Routing Algorithms

• Non-Adaptive: Shortest-path routing, Flooding.
• Adaptive: Distance-Vector, Link-State Routing.

Congestion Control

• Open Loop: Prevents congestion before it happens.
• Closed Loop: Mitigates congestion after it occurs.

Addressing

• IPv4 Subnetting: Dividing networks into subnets.
• IPv6 Transition: Dual stack, Tunneling, Header translation.

UNIT IV: Transport Layer

Transport Protocols

• TCP: Reliable, connection-oriented protocol.
• UDP: Unreliable, connectionless protocol.

Connection Management

• Establishment: Three-way handshake.
• Termination: Four-step process.

Flow and Error Control

• Flow Control: Sliding Window Protocol.
• Error Control: Acknowledgment and retransmission.

UNIT V: Application Layer

Application Paradigms

• Client-Server Model: Centralized service provision.
• Peer-to-Peer Model: Decentralized, equal node roles.

Protocols and Services

• HTTP: Foundation of the World Wide Web.
• DNS: Domain Name System, maps domain names to IP addresses.
• SMTP: Simple Mail Transfer Protocol for email.

Security

• RSA Algorithm: Public key cryptography for secure communication.