OSI model

                              OSI  MODEL


Introduction to OSI Model




~ OSI model is based o the proposal developed by
the international standards organizatin(ISO).

~ This model is called ISO OSI (Open Systems Interconnection) Reference model because it deals with connecting open systems (systems that are open for communication with other systems).

~ We call it as OSI Model.




Physical layer :
                                               
                           *  Provides physical interface for transmisssion of information.

* Define rules by which bits are passed from one system to another on a physical communication medium.


Data link layer :


                                      * data linl layer attempts to provide reliaable communication over the phycial layer interface.
 * Breaks the out going data into frames the reassemble the recived frames.


Network layer :

           
                                     * Implements routing of frames (packets) through the networks.
* Define the most optimum path the packet should take from the source to the destination.
* Defines logical addressitng so that any end point can be identified.

Transport layer :


                                           * Propose of this layer is to provide a reliable mechanism for the exchange of data between two processes in diffrent computer.
* Ensure that the data units are delivered error free.
* Ensure that data units are delivered in sequence.
* Ensure that there is no loss or duplication of data units.

Screen layer :

                      * Session layer provides mechanism for controlling the dialogue between the two end system. it defines how to start, control and end conversations (called session) between applications.
* This layer request for the logical connection to be established on an end user's request.

Presentation layer :

                                                     * Presentation layer defines the format in which the is to be exchanged between the two communicating entities.
*Also handels data compression and data encryption (cryptography).


Application layer :

                                                  * Application layer intracts with Application programs ans is the higest level of ISO model.
Application layer contains menagement function to support distributed applications.
* Example of application layer are applications such as file transfer.
electronic mail, remote login etc...

Comments

Letest Tricks

Beginner's Guide To The Deep Web and The Dark Web

How to make deposit via Bitcoin on OlympTrade

Wibr+ WiFi Hacking Tool For Android