GLOSSARY
111
V.22 bis
An ITU-T standard for modem communications at 2400
bps. The standard includes an automatic link negotiation
fallback to 1200 bps and compatibility with Bell
212A/V.22 modems.
V.27 ter
An ITU-T standard for facsimile operations that specifies
modulation at 4800 bps, with fallback to 2400 bps.
V.29
An ITU-T standard for facsimile operations that specifies
modulation at 9600 bps, with fallback to 7200 bps.
V.32
An ITU-T standard for modem communications at 9600
bps and 4800 bps. V.32 modems fall back to 4800 bps
when line quality is impaired.
V.32 bis
An ITU-T standard that extends the V.32 connection
range: 4800, 7200, 9600, 12,000, and 14,400 bps. V.32 bis
modems fall back to the next lower speed when line
quality is impaired, fall back further as necessary, and also
fall forward (switch back up) when line conditions
improve (see online fall back/fall forward).
V.34
An ITU-T standard that currently allows data rates as high
as 28,800 bps.
V.34+
An enhancement to V.34 that enables data transfer rates as
high as 33,600 bps.
V.42
An ITU-T standard for modem communications that
defines a two-stage process of detection and negotiation
for LAPM error control.
V.42 bis
An extension of ITU-T V.42 that defines a specific data
compression scheme for use during V.42 connections.