4
G
LOSSARY
For example, at 2400 bps, 8-bit characters with start and stop bits (for
a total of ten bits per character) will be transmitted at a rate of
approximately 240 characters per second (cps). Some protocols, such as
USR HST and MNP, employ advanced techniques such as longer
transmission frames and data compression to increase cps.
Class 1/EIA-57
An American standard used between facsimile application programs
and facsimile modems for sending and receiving Class 1 faxes.
Class 2.0/EIA-59
An American standard used between facsimile application programs
and facsimile modems for sending and receiving Class 2.0 faxes.
CO
See central office.
COM port
See serial port, EIA-232.
cps
See characters per second.
CPU
Central processing unit.
CRC
See cyclic redundancy check.
cyclic redundanc
check (CRC)
An error-detection technique consisting of a cyclic algorithm performed
on each block or frame of data by both sending and receiving
modems. The sending modem inserts the results of its computation in
each data block in the form of a CRC code. The receiving mode
compares its results with the received CRC code and responds with
either a positive or negative acknowledgment. In the ARQ protocol
implemented in 3Com high speed modems, the receiving modem
accepts no more data until a defective block is received correctly.
data communications
A type of communications in which computers and terminals are able
to exchange data over an electronic medium.
data compression
When the transmitting modem detects redundant units of data, it
recodes them into shorter units of fewer bits. The receiving mode
then decompresses the redundant data units before passing them to
the receiving computer.
data compression
table
A table of values assigned for each character during a call under data
compression. Default values in the table are continually altered and
built during each call: the longer the table, the more efficient
throughput gained
Summary of Contents for Courier
Page 12: ......
Page 28: ...1 14 CHAPTER 1 CONNECTING TO YOUR ISP ...
Page 36: ...3 4 CHAPTER 3 UPGRADING YOUR MODEM ...
Page 58: ...6 6 CHAPTER 6 WORKING WITH MEMORY ...
Page 64: ...8 4 CHAPTER 8 CONTROLLING EIA 232 SIGNALING ...
Page 72: ...9 8 CHAPTER 9 ACCESSING AND CONFIGURING THE COURIER V EVERYTHING MODEM REMOTELY ...
Page 80: ...10 8 CHAPTER 10 CONTROLLING DATA RATES ...
Page 96: ...12 6 CHAPTER 12 FLOW CONTROL ...
Page 108: ...13 12 CHAPTER 13 HANDSHAKING ERROR CONTROL DATA COMPRESSION AND THROUGHPUT ...
Page 112: ...14 4 CHAPTER 14 DISPLAYING QUERYING AND HELP SCREENS ...
Page 122: ...15 10 CHAPTER 15 TESTING THE CONNECTION ...
Page 142: ...17 8 CHAPTER 17 TROUBLESHOOTING ...
Page 156: ...A 14 APPENDIX A S REGISTERS ...
Page 172: ...B 16 APPENDIX B ALPHABETIC COMMAND SUMMARY ...
Page 178: ...C 6 APPENDIX C FLOW CONTROL TEMPLATE ...
Page 186: ...E 4 APPENDIX E V 25 BIS REFERENCE ...