Consider a simple UDP-based protocol for requesting files (based somewhat loosely on the Trivial File Transport Protocol [TFTP]). The client sends an initial file request, and the server answers (if the file can be sent) with the first data packet. Client and server then continue with a stop-and-wait transmission mechanism.

(a) Describe a scenario by which a client might request one file but get another; you may allow the client application to exit abruptly and be restarted with the same port.

(b) Propose a change in the protocol that will make this situation much less likely.