OSI Model Session & Presentation Layer | Computer Networks Tutorial

Session Layer : OSI Model

  • The Session Layer is the 5th layer of OSI Model and it provides appropriate sessions between users and software where users interacts.
  • This layer can be used on the basis of resources available and it can be skipped too if not requires(TCP/IP model skips this layer as it not much of use).
  • The Session Layer deals with the establishment and management of sessions among the application software keeping the user personal data away.
  • For example : Login session in IRCTC train reservation portal or Online payment session.

Session Layer : Functions & Features

  • These are some of the major feature performed by Session Layer:
    • Connection establishment.
    • Connection termination.
    • Synchronization.
    • Dialog control.
This image describes the architecture and working of session layer in computer networks.
Session Layer : Architecture

Presentation Layer : OSI Model

  • The Presentation Layer is the 6th layer of OSI Modeland it provides appropriate representation of data through various data presentation technique.
  • Whenever data transmission takes place, it might be possible that data on sender’s end might look different or might not support at receiver end. So, Presentation Layer ensures that data presented in same format at both sender’s and receiver’s end.

Presentation Layer : Functions & Features

  • The Presentation Layer ensures that translation of data among different devices. So, irrespective of the devices used, presentation layer ensures data must be presented similarly on all those devices.
  • Data encryption and data decryption are other features of presentation layer.
  • Data compression technique is another major feature of this layer.
This image describes the architecture and working of presentation layer in computer networks.
Presentation Layer : Architecture