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Presentation Layer

Presentation Layer(Layer 6): It is concerned with the syntax and semantics of the information exchanged between two systems, translation of data between a networking service and an application; including character encoding, data compression, and encryption/decryption. 
Functions of the Presentation layer include:
  • Translation: As different computers use different encoding systems, the Presentation layer is responsible for the interoperability between these different encoding methods. The Presentation layer at the sender changes the information from its sender dependent format to a common format. The Presentation layer at the receiving machine changes the common format into its receiver dependent format.
  • Encryption: Encryption means sender transforms the original information to another form and sends the resulting message out over the network.
  • Compression: Data compression reduces the number of bits contained in the information which is particularly important in the transmission of multimedia as video, audio, text, etc 
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