Chapter Questions
What is the difference between a terminal protocol and a data link protocol?
What is the purpose of data sequencing in which a large block is broken into smaller blocks for transmission?
Define the characteristics of a teletypewriter protocol.
What is the purpose of using one or more null characters after a carriage return, line feed sequence?
What error detection method is used in the teletypewriter protocol? How are errors corrected when they are detected?
What is echoplex? When echoplex is used who is responsible for examining locally printed characters?
How can a receiver detect the occurrence of an error when the XMODEM protocol is used?
x Discuss three limitations of the XMODEM protocol.
What is the difference between the XMODEM and XMODEM/CRC file transfer protocols? Which provides a more reliable method of error detection and correction?
Describe why a communications program can provide a display of the status of a file transfer operation when the YMODEM protocol is used.
Under what conditions should you consider the use of the YMODEM-G or YMODEM-G batch protocols?
How does the ZMODEM protocol provide an extended error detection capability?
What are the major differences between the 2780,3780 and 3270 protocols?
What is the purpose of a bisynchronous protocol transmitting alternating acknowledgements (DLE1 and DLEO)?
How does the DDCMP protocol provide data transparency?
Assume that the response field of a NAK message in a DDCMP protocol has a value of 14 and messages $12,13,14,15$ and 16 are outstanding. What does this indicate?
What is the purpose of the HDLC flag? How is its integrity protected?
What is the advantage of a selective reject command?