PRESENTATION LAYER
It receives information
from the application layer protocols and puts it into a format that all
computers following the OSI model can understand.
It means that when a
user constructs a word document in MS-word, while the receiver computer has
only start office, so the receiver can’t open that file. But due to
presentation layer he is able to open that.
It a user uses a Corel
presentation to save a graphic, the presentation layer convert the graphic into
a Tagged Image File Format (TIFF), Graphic Interchange Format (GYF) of Joint Photographic
Experts Group (JPEG) format. This way if the user sends this graphic to another
who does not have the Corel application the user’s O/S still present the
graphic because it has been into a standard format. i.e it works as a
TRANSPORT, which translates the format and application is using to a standard
format used for passing manages over a network.
The
presentation layer negotiates and establishes the format the format in which
data is exchanged. The main function performed by this layer are:-
i. A) Translation
ii. B)Encryption
iii. C)Decryption
iv. D)Data
compression
v. E)Decompression
