Notes

Complete topics for Computer Networks-
Overview of Computer Networks
Computer networks are essential for enabling communication between devices, allowing for data sharing and resource utilization. This summary provides chapter-by-chapter notes derived from various academic resources on computer networks.
Chapter 1: Introduction to Computer Networks
Definition: A computer network is a collection of autonomous computers interconnected to share information and resources.
Types of Networks:
LAN (Local Area Network): Covers a small geographical area, such as a building.
WAN (Wide Area Network): Spans a large geographical area, connecting multiple LANs.
MAN (Metropolitan Area Network): Covers a city or a large campus.
Chapter 2: Reference Models
OSI Model: Comprises seven layers (Application, Presentation, Session, Transport, Network, Data Link, Physical). Each layer serves specific functions and communicates with the same layer on another machine.
TCP/IP Model: A four-layer model (Application, Transport, Internet, Link) that simplifies the OSI model while focusing on the protocols used in the Internet.
Chapter 3: Physical Layer
Functions: Deals with the physical connection between devices and the transmission of raw bitstreams over a physical medium.
Transmission Media:
Guided Media: Includes cables like twisted pair and fiber optics.
Unguided Media: Involves wireless transmission methods such as radio waves.
Chapter 4: Data Link Layer
Purpose: Provides node-to-node data transfer and handles error detection and correction.
Protocols:
Ethernet: A widely used LAN technology that defines how data packets are formatted and transmitted.
Multiple Access Protocols: Includes ALOHA, CSMA/CD (used in Ethernet), and CSMA/CA (used in wireless networks).
Chapter 5: Network Layer
Responsibilities: Manages device addressing, tracks the location of devices on the network, and determines the best way to route data packets.
Protocols:
IP (Internet Protocol): Responsible for addressing and routing packets across networks.
Routing Protocols: Such as OSPF (Open Shortest Path First) and BGP (Border Gateway Protocol), which determine optimal paths for data transmission.
Chapter 6: Transport Layer
Functionality: Ensures complete data transfer with mechanisms for error recovery and flow control.
Protocols:
TCP (Transmission Control Protocol): Provides reliable, ordered delivery of a stream of bytes.
UDP (User Datagram Protocol): Offers a connectionless service for applications that require speed over reliability.
Chapter 7: Application Layer
Role: Interfaces directly with end-user applications to provide network services.
Common Protocols:
HTTP (Hypertext Transfer Protocol): Used for transferring web pages.
FTP (File Transfer Protocol): Facilitates file transfers between computers.
DNS (Domain Name System): Resolves domain names to IP addresses.
Chapter 8: Emerging Trends
Discusses advancements in networking technologies such as IPv6 adoption, network security measures including encryption methods, and the rise of cloud computing services.
These notes encapsulate foundational concepts in computer networking, emphasizing critical protocols and their functionalities across different layers of network architecture. For detailed study, refer to textbooks such as "Computer Networks" by Andrew S. Tanenbaum or "Data Communications and Networking" by Behrouz A. Forouzan.