Practical 4
AIM:
To compare the OSI and TCP/IP protocol models.
OSI Model
The OSI (Open Systems Interconnection) model is a seven-layer framework that defines how data is transmitted across a network, providing a theoretical foundation for understanding network communication. Created by the International Organization for Standardization (ISO) in 1984, the OSI model is non-proprietary and divides communication tasks into the following layers:
- Physical Layer
- Data Link Layer
- Network Layer
- Transport Layer
- Session Layer
- Presentation Layer
- Application Layer
The OSI model is generally not implemented fully in real-world networking hardware or software but serves as a conceptual guideline for network architecture and protocol design.
TCP/IP Model
The TCP/IP (Transmission Control Protocol/Internet Protocol) model is a four-layer framework essential for data communication over networks, especially the Internet. Developed by the Department of Defense (DoD) in the 1960s, it simplifies communication into four layers:
- Link Layer
- Internet Layer
- Transport Layer
- Application Layer
Unlike the OSI model, TCP/IP is widely implemented in practical networking systems, focusing on ensuring reliable and accurate data transmission across devices.
Comparison Between OSI and TCP/IP Models
| SR. NO | OSI Model (Open System Interconnection) | TCP/IP Model (Transmission Control Protocol) |
|---|---|---|
| 1 | Stands for Open System Interconnection. | Stands for Transmission Control Protocol. |
| 2 | Comprises seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. | Comprises four layers: Link, Internet, Transport, and Application. |
| 3 | Less commonly used in practical applications. | Widely used, especially for Internet communications. |
| 4 | Transport layer ensures packet delivery. | Transport layer does not ensure packet delivery. |
| 5 | Follows a vertical approach. | Follows a horizontal approach. |
| 6 | Easier to replace or update components. | Components are more difficult to replace compared to OSI. |
| 7 | Serves as a reference model for network design and protocols. | An implemented model of OSI, providing practical network functionality. |
| 8 | Network layer offers both connection-oriented and connectionless services. | Network layer provides only connectionless services. |
| 9 | Less reliable due to theoretical design. | More reliable, with protocols that directly support implementation. |
| 10 | Standardizes hardware like routers, switches, and motherboards. | Focuses on creating connections between devices without hardware standardization. |
| 11 | Distinguishes between services, protocols, and interfaces. | Does not distinguish between services, protocols, and interfaces. |