Book Image

Understanding TCP/IP

By : CP Books a.s.
Book Image

Understanding TCP/IP

By: CP Books a.s.

Overview of this book

This book covers in detail the Open System Interconnection (OSI) reference model and the TCP/IP protocols that operate that different layers. Its coverage includes various application protocols. The authors explain in an easy-to-read style networking concepts and protocols, with examples that make the book a practical guide in addition to its coverage of theory.
Table of Contents (20 chapters)
19
Index

13.7 Abnormal Termination of Data Transfer

Abnormal termination of a data transfer is practically the only use of the Telnet protocol commands (NVT protocol) by FTP.

In Table 13.3, we can find the ABOR command that is used for an abnormal termination of the previously executed command. It could happen that the server would sequentially process individual client commands one by one. In such a case, the ABOR command would be processed after the completion of the previous command. But we would usually want to terminate the previous (running) command sooner, i.e., to process the command ABOR immediately when the server receives it. This can be achieved as follows:

The client software is generally sensitive to some key sequence for abnormal termination, for example, Ctrl + C (graphical clients can have a single button for termination). After pressing Ctrl + C, the client would like the server to stop sending data into the data channel. The client accomplishes this with two actions:

  1. With the help...