JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD MCA 2021 COMPUTER NETWORKS Previous Question Paper (July/August - 2021 - R17)

The TCP/IP reference model is a practical framework developed by the Department of Defense (DoD) to interconnect networks. It is organized into four hierarchical layers, each responsible for specific communication tasks:

1. Application Layer: Contains high-level protocols such as HTTP, FTP, SMTP, and DNS. It allows user applications to access the network services.
2. Transport Layer: Responsible for end-to-end communication. It uses TCP for reliable, connection-oriented data delivery or UDP for fast, connectionless delivery.
3. Internet Layer: Handles addressing and routing of packets across multiple networks using the Internet Protocol (IP). It determines the best path for data to reach the destination.
4. Network Access Layer (or Link Layer): Manages the physical transmission of data between nodes on the same network. It handles hardware addressing and framing, interacting directly with the physical medium.

Diagram representation:

Unlike the OSI model, which is theoretical, the TCP/IP model is the foundation of the modern internet. It emphasizes interoperability and robustness, combining the physical and data link layers into a single Network Access layer and grouping the session, presentation, and application layers into a single Application layer.