*OSI MODEL

Created By Wasim Akram

OSI Model

• Open System Interconnection

• This divides the networks into the 7 layers

• The protocol perform services to unique layers

• Protocol interacts with protocol in Layer Directly above and below

• Protocol : it is a set of instruction to perform a function or group of function that is written by a programmer

*OSI Model

*How to Recall 7 Layers

* Everything in the world have a way to learn and understand and same he for the OSI layer

*“ All People Seems To Need Data Progress”

*Just took the first alphabet in the word in given sentence

*7 Osi models

* All – Application Layer

* People – Presentation Layer

*Seems – Session Layer

*To – Transport Layer

*Need – Network Layer

*Data – Data Link Layer

*Progress – Presentation Layer

*Application Layer

*Application Layer is responsible using network application like HTTP, FTM, Directory Services.

*Application program interface (API) – set of routines that make up part of a software application

*Presentation Layer

*It is responsible for Data Exchange between 2 devices

*It manages data encryption and decryption

* Translation and Compression

*Session Layer

* It is responsible for establishment of connections.

*Management, Synchronization, Termination between two nodes

*Dialog Control

*Transport Layer

*It ensures that the entire massage reached to the receiver or not

* Service point addressing

*Segmentation & Reassembling

*Connection Control

*Flow Control

*Error Control

*Network Layer

• It is responsible for logical addressing

• Routing

• Handling Congestion Issues

• Internetworking

*Data Link Layer

*It handle Data Transfer

*Framing

*Physical Addressing

* Access Control

* Flow Control

* Error Control

*Physical Layer

*It is responsible for Establishment or Termination of the connection between two nodes.

* Media Characteristics

* Data Encoding

* Transmission Mode

*The End