12-2
C
HAPTER
12: H
ANDSHAKING
, E
RROR
C
ONTROL
, D
ATA
C
OMPRESSION
,
AND
T
HROUGHPUT
Selective Reject is an optional part of the ITU-T V.42 (LAPM) standard.
Attaining Speeds Above 28.8 Kbps
V.34 connections at 21.6, 24, and 26.4 Kbps are common. To get
connections of 28.8, 31.2, and 33.6 Kbps, line quality must be pristine
end-to-end. In addition, 31.2 and 33.6 Kbps connection rates are
possible only when the device to which you are connecting also runs
software that supports speeds above 28.8 Kbps.
Attaining 56 K Connections
When a client x2 modem connects to a server x2 modem, the path
through the telephone network between the modems is subject to the
following conditions for an x2 connection to be made.
A digital connection at one end.
ISPs or other online services must
have a digital connection to the public switched telephone network
(PSTN). Most major online services have a digital connection to the PSTN.
Only one digital-to-analog conversion.
There can be only one
digital-to-analog conversion in the telephone network between the x2
server modem and the x2 client modem.
Controlling the V.8 Call Indicate Tone
The V.8 protocol speeds call negotiation and specifies a call indicate tone.
Providing the call indicate tone is optional. For compatibility, we ship the
Business Modem with the call indicate tone disabled.
For your modem to
Command
Enable Selective Reject
ATS51.6=0
(Default)
Disable Selective Reject
ATS51.6=1
For your modem to
Command
Enable the call indicate tone
ATS54.6=0
Summary of Contents for OfficeConnect 56K Business
Page 14: ...4 ABOUT THIS GUIDE ...
Page 32: ...1 18 CHAPTER 1 CONNECTING TO YOUR ISP ...
Page 42: ...3 6 CHAPTER 3 MODES OF OPERATION ...
Page 64: ...7 4 CHAPTER 7 CONTROLLING EIA 232 SIGNALING ...
Page 72: ...8 8 CHAPTER 8 CONTROLLING DATA RATES ...
Page 80: ...9 8 CHAPTER 9 ACCESSING AND CONFIGURING THE BUSINESS MODEM REMOTELY ...
Page 96: ...11 6 CHAPTER 11 FLOW CONTROL ...
Page 108: ...12 12 CHAPTER 12 HANDSHAKING ERROR CONTROL DATA COMPRESSION AND THROUGHPUT ...
Page 112: ...13 4 CHAPTER 13 DISPLAYING QUERYING AND HELP SCREENS ...
Page 124: ...14 12 CHAPTER 14 TESTING THE CONNECTION ...
Page 132: ...15 8 CHAPTER 15 TROUBLESHOOTING ...
Page 162: ...B 14 APPENDIX B ALPHABETIC COMMAND SUMMARY ...
Page 168: ...C 6 APPENDIX C FLOW CONTROL TEMPLATE ...
Page 210: ...14 GLOSSARY ...