<P> In many widely used applications and protocols, no distinction is made between the presentation and application layers . For example, HyperText Transfer Protocol (HTTP), generally regarded as an application - layer protocol, has presentation - layer aspects such as the ability to identify character encoding for proper conversion, which is then done in the application layer . </P> <P> Within the service layering semantics of the OSI network architecture, the presentation layer responds to service requests from the application layer and issues service requests to the session layer . </P> <P> In the OSI model: the presentation layer ensures the information that the application layer of one system sends out is readable by the application layer of another system . For example, a PC program communicates with another computer, one using extended binary coded decimal interchange code (EBCDIC) and the other using ASCII to represent the same characters . If necessary, the presentation layer might be able to translate between multiple data formats by using a common format . </P> <Ul> <Li> Data conversion </Li> <Li> Character code translation </Li> <Li> Compression </Li> <Li> Encryption and Decryption </Li> </Ul>

In the osi model which of the following functions are performed at the presentation layer