Which layer of the TCP/IP stack is responsible for applications running on different hosts?

The Application layer is the topmost layer of the TCP/IP stack and is specifically responsible for enabling applications running on different hosts to communicate with each other. This layer provides the necessary protocols and standards that applications use to access network services. Examples include HTTP for web browsing, FTP for file transfers, and SMTP for email transmission.

By facilitating communication directly between software applications, the Application layer manages various functions essential for users, such as windowing and session management. It abstracts the details of data transmission from the user, allowing for seamless interaction between software applications regardless of the underlying network technology being used.

Understanding this layer's role is fundamental in grasping how different software applications operate and communicate over a network, which is crucial for tasks such as troubleshooting, development, and network design.