CS 3591 - Computer Networks Notes

CS 3591 - Computer Networks Notes

Course Objectives

  • Understanding layering in networks.

  • Functions of protocols in the TCP/IP protocol suite.

  • Visualizing end-to-end flow of information.

  • Functions of the network layer and various routing protocols.

  • Familiarization with functions and protocols of the transport layer.

Unit I - Introduction and Application Layer

Key Concepts

  • Data Communication and Networks:

    • Networks: Interconnected devices for data exchange.

    • Types of Networks: Local Area Network (LAN), Wide Area Network (WAN), Metropolitan Area Network (MAN).

  • Protocol Layering: Structure of network protocols.

  • TCP/IP Protocol Suite: Framework for internet communications.

  • OSI Model: A conceptual model that standardizes communication functions.

  • Sockets: Endpoint connections for communication.

Application Layer Protocols

  • HTTP: Web communication.

  • FTP: File transfer.

  • Email Protocols: SMTP, POP3, IMAP, and MIME for email handling.

  • DNS: Domain Name System for resolving domain names.

  • SNMP: Simple Network Management Protocol for network management.

Unit II - Transport Layer

Transport Layer Protocols

  • UDP: User Datagram Protocol for connectionless service; low overhead, no error recovery.

  • TCP: Transmission Control Protocol; reliable, connection-oriented, supports flow control.

    • Connection Management: Three-way handshake for establishing connections.

    • Flow Control: Prevents overwhelming of the receiver.

    • Congestion Control: Techniques like DECbit and RED to manage network traffic.

    • SCTP: Stream Control Transmission Protocol; supports multiple streams and messages.

Unit III - Network Layer

Functions of the Network Layer

  • Switching: Process of transmitting data packets within networks.

  • Routing: Determining optimal paths for data transmission.

  • IP Addressing: Unique addresses for devices on a network.

    • IPv4: 32-bit addressing scheme with a limit of 4.3 billion addresses.

    • IPV6: 128-bit addressing, designed to replace IPv4 for addressing growth.

  • Protocols: ARP, RARP & ICMP for address resolution and error messaging.

Unit IV - Routing

Routing Protocols

  • Unicast Routing: Direct communication via routing tables.

    • Distance Vector Routing (RIP): Each node shares distances to neighbors.

    • Link State Routing (OSPF): Nodes maintain a complete view of the network.

    • Path-Vector Routing (BGP): Manages routes in a policy-driven manner for ASs.

  • Multicast Routing: Efficiently delivers packets to multiple recipients using DVMRP and PIM protocols.

Unit V - Data Link and Physical Layers

Data Link Layer

  • Framing: Dividing data into manageable frames for transmission.

  • Flow Control and Error Control: Mechanisms ensuring reliable transmission.

    • Sliding Window protocols (e.g., HDLC, PPP), ARQ mechanisms such as Stop-and-Wait, Go-Back-N, and Selective Repeat.

Physical Layer

  • Transmission Media: Types include twisted pair, coaxial, and fiber-optic cables.

  • Performance metrics: Data rate, signal strength, and transmission distance considerations.

Network Technologies

  • Ethernet Basics: Standard protocols for wired networks; uses CSMA/CD for collision detection.

  • Wireless LAN (802.11): Wireless communication standards and protocols; utilizes CSMA/CA for collision avoidance.

Conclusion

  • Comprehensive understanding of networking principles, protocols, and layers crucial for building and managing efficient networks. Knowledge of both TCP/IP and OSI models enhances problem-solving in network design and administration.