OSI vs Internet Protocol Model - CSU359 - Shoolini University

OSI vs TCP/IP (Internet Protocol) Model

2024, August 10

OSI Model

Full Name: Open Systems Interconnection Model

Layers: 7 layers

Purpose: To provide a standard for different computer systems to communicate over a network.

Development: Developed by the International Organization for Standardization (ISO).

Layers:

  1. Physical Layer: Transmits raw bit stream over the physical medium. Examples: Ethernet cables, hubs.
  2. Data Link Layer: Provides node-to-node data transfer and error correction. Examples: Switches, MAC addresses.
  3. Network Layer: Manages device addressing, tracks the location of devices on the network, and determines the best way to move data. Examples: Routers, IP addresses.
  4. Transport Layer: Provides reliable data transfer services to the upper layers. Examples: TCP, UDP.
  5. Session Layer: Manages sessions between applications. Examples: RPC, PPTP.
  6. Presentation Layer: Translates data between the application layer and the network format. Examples: Encryption, ASCII, JPEG.
  7. Application Layer: Provides network services to the end-users. Examples: HTTP, FTP, SMTP.

Internet Protocol (TCP/IP) Model

Full Name: Internet Protocol Suite (Transmission Control Protocol/Internet Protocol)

Layers: 4 layers

Purpose: To enable diverse computer networks to interconnect and communicate through a common language.

Development: Developed by the U.S. Department of Defense.

Layers:

  1. Link Layer: Corresponds to the OSI model’s physical and data link layers. Examples: Ethernet, Wi-Fi.
  2. Internet Layer: Corresponds to the OSI model’s network layer; handles logical addressing and routing. Examples: IP, ICMP.
  3. Transport Layer: Corresponds to the OSI model’s transport layer; provides end-to-end communication services. Examples: TCP, UDP.
  4. Application Layer: Corresponds to the OSI model’s session, presentation, and application layers; provides network services to the applications. Examples: HTTP, FTP, SMTP.

Comparison Table

Feature OSI Model Internet Protocol (TCP/IP) Model
Number of Layers 7 4
Development Developed by ISO Developed by the U.S. Department of Defense
Layer Names Physical, Data Link, Network, Transport, Session, Presentation, Application Link, Internet, Transport, Application
Layer Functions Detailed and specific functions per layer More generalized functions per layer
Usage Mainly used as a teaching tool and conceptual model Widely used in practical networking
Protocol Examples Ethernet, IP, TCP, HTTP Ethernet, IP, TCP, HTTP
Reliability More reliable due to the specific functionalities at each layer Reliable but less detailed at some layers

Practical Scenarios

OSI Model

Used in academic environments for teaching networking concepts and understanding the detailed functioning of networks.

TCP/IP Model

Used in real-world networking, including the internet and most modern network implementations.