Which layer of the OSI model is responsible for data encryption?

The presentation layer of the OSI model is tasked with data encryption, among other responsibilities. This layer serves as a translator between the application layer and the network layer, ensuring that data is properly formatted for its destination. One of its key functions includes the transformation of data formats, which can involve converting data into a form that is secure and suitable for transmission.

Encryption occurs at the presentation layer because it deals with the data representation, making it possible to protect sensitive information before it is transmitted over the network. It is essential for ensuring data confidentiality, integrity, and authentication during communication. Common examples of protocols that operate at this layer and provide encryption include Secure Sockets Layer (SSL) and Transport Layer Security (TLS), which are used in secure web communications.

In contrast, the responsibilities of other layers, such as the application, transport, and network layers, do not focus primarily on data encryption. The application layer is primarily concerned with providing network services to end-user applications, the transport layer deals with data transfer between hosts and ensuring complete data delivery, and the network layer is responsible for routing packets through the network. Thus, the presentation layer is correctly identified as the layer that handles data encryption.