Consider a simple UDP-based protocol for requesting files (based somewhat loosely on the Trivial File Transport Protocol, or 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.

Consider a simple UDP-based protocol for requesting files (based somewhat loosely on the Trivial File Transport Protocol, or 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.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Question

Consider a simple UDP-based protocol for requesting files (based
somewhat loosely on the Trivial File Transport Protocol, or 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.

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