What does the session layer primarily ensure during data transmission?

• A. Data correctness
• B. Stable communication between devices
• C. Effective routing of packets
• D. Error detection and correction

Answer: (B)

The session layer, which is the fifth layer of the OSI (Open Systems Interconnection) model, is primarily responsible for establishing, managing, and terminating sessions between applications. Its main role is to ensure stable communication between devices by managing the exchange of information over a period, including opening and closing connections as well as maintaining the session’s state. This allows applications across different devices to communicate effectively, regardless of their underlying network structures or protocols.

While other layers in the OSI model are responsible for tasks like error detection and correction, which fall under the realms of the transport layer and data link layer, the session layer's key focus is to provide a reliable connection for data exchange, ensuring that the communication sessions are properly maintained throughout their duration. Therefore, the session layer plays a critical role in enabling smooth and reliable communication, making it essential for maintaining ongoing interactions between connected applications.