OSI Reference Model

2.5. Presentation Layer

6. Presentation Layer (Layer 6)

Function: Translates data between the application layer and lower layers, ensuring it’s in a usable format. Handles encryption, compression, and data formatting.

Key Responsibilities:

Converts data formats (e.g., ASCII to EBCDIC).

Encrypts and decrypts data (e.g., for secure communication).

Compresses data to reduce transmission size.

Manages character encoding and file formats.

Examples:

Protocols: SSL/TLS, MIME (Multipurpose Internet Mail Extensions).

Formats: JPEG, PNG, GIF, XML, JSON.

Example: Encrypting data for HTTPS or compressing video for streaming.

Analogy: A translator converting a message into the recipient’s language or securing it for privacy.