Presentation Layer:

Presentation Layer:

It perform the following functions

1. Data Reformatting: When two computers exchange data, the data is changed to bit streams before it is transmitted. The computers may use different encoding techniques. The presentation layer at sending computer changes data according to the sender’s format. The presentation layer at receiving computer changes data according to the receiver’s format.
2. Encryption: The presentation layer encrypts data before transmission. It means that the sender transform the original information to another form and sends resulting message over the network. The receiver again transforms the message back to its original form. It is called decryption.
3. Compression: Data compression reduces the number of bits to be transmitted. The presentation layer compresses a large amount of data into small size.