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OSI Model

A conceptual framework used to understand and standardize the functions of a telecommunication or computing system into seven abstraction layers.

AbbreviationOSI
Categorynetwork

Overview

The Open Systems Interconnection (OSI) model was developed by the ISO to provide a standard for different computer systems to communicate. It divides network communication into seven distinct layers, each with specific responsibilities.

The Seven Layers

  1. Physical Layer: Hardware, cables, and bit transmission.
  2. Data Link Layer: MAC addressing and error detection on the local link.
  3. Network Layer: IP addressing and routing.
  4. Transport Layer: End-to-end communication and error recovery (TCP/UDP).
  5. Session Layer: Managing sessions between applications.
  6. Presentation Layer: Data translation, encryption, and compression.
  7. Application Layer: User interface and network services (HTTP, FTP).

Importance

  • Interoperability: Allows different vendors' products to work together.
  • Troubleshooting: Helps isolate network problems to specific layers.
  • Education: Provides a common language for networking professionals.

Related Terms

TCP/IP ModelPhysical LayerApplication Layer