Presentation Layer
As we know, the OSI model layer has 7 layers and it is number 6 in layers. It is the layer between the application layer and the session layer and its function is to access all the information coming from the session layer.
After checking its accuracy, then after defining it well, all the information has to be presented to the application layer in its standardized format (standardized format).
When a machine sends any collected information to another machine, the syntax layer keeps in mind that the machine receiving all the information can understand the information and can also use all that information.
Meaning that the presentation layer plays the role of a translator or translator in the OSI model layer.
The presentation layer is also called the syntax layer, as its main function is to take care of the syntax and semantics of the information exchanged between any two communication systems. syntax means grammar and semantics mean semantics.
How A Presentation Layer Works
This layer works by converting all the information into a variety of file formats and forms of encryption.
The syntax layer is able to do these using built-in algorithms and is able to standardize the information whether it can be handled by XML, C++, or TLV.
In addition to passing all the information from the application layer to the session layer, the presentation layer is also responsible for passing information from the session layer to the application layer.
Functions of Presentation Layer
- Character-Code Translation
- Data Conversion
- Data Compression
- Data Encryption and Decryption
- Data Translation
- Graphic handling
Character-Code Translation –
It stores all the information given by the computer user in a different way, for example in some computers American standard code for information interchange (ASCII) code is used then in some computers Extended binary code decimal interchange code (EBCDIC) is used.
The syntax layer can translate ASCII into EBCDIC if needed.
Data Conversion –
It is responsible for changing the type of layer data for example it converts integer numbers to floating point numbers.
Data Compression –
It is able to compress the data by compressing it so that they can be transferred much faster.
Data Encryption and Decryption –
While transferring data in the network field, Data Encryption is required to keep all that information from hackers. Similarly, once the data reaches its destination user, there is a need to decryption it so that the usage of that data can be used.
The Presentation Layer facilitates data information encryption and decryption so that the user can be protected from hackers.
Data Translation –
We can connect different types of computers, laptops, mobiles, tablets, printers, screeners, servers and mainframes etc. using the network. All these computers use different types of Programming Language, Operating System and Language.
In such a situation, when one computer sends any information to another computer, then the data sent by it can be understood by another machine, so it is very important that the information of both computers is presented in the correct language to its destination computer.
The presentation layer acts as a translator that presents information to machines in understandable language.
Graphic handling –
It also presents various types of graphic such as images, videos etc. in an understandable format.
Protocols Supported at Presentation
- Independent Computing Architecture (ICA)
- Apple Filing Protocol (AFP)
- NetWare Core Protocol
- Network Data Representation
Independent Computing Architecture (ICA) –
The Independent Computing Architecture is a designed protocol for syntax server systems.
Network Data Representation –
It makes it understandable by correcting the syntax or grammar of the information received through the network.
Apple Filing Protocol (AFP) –
We are used to exchange data files of computers.
NetWare Core Protocol –
It was created by a company named Novell Inc, which uses it in its client-server operating system.
Advantages of presentation layer
The presentation layer is advantageous because it is able to handle all the data for an application before sending the information to the session layer. Since the session layer does not modify the actual data it receives, that is important is the syntax layer converts the data into the appropriate format and then encrypts it for confidentiality and authentication.