V42bis | Article about V42bis by The Free Dictionary
V.42bis (redirected from V42bis)
V.42bis (communications, standard)
An extension of the ITU-T V.42
standard modem protocol
to included compression
Lempel-Ziv related technique, which detects frequently
occurring character strings and replaces them with tokens.
This is similar to the Unix compress
for text is 50% or better; with nearly 20% gain
conversion this gives reduces transmission
time by almost 60%.
V.42bisAn ITU standard (1989) for analog modem data compression. It uses the BTLZ technique to achieve up to a 4:1 ratio. V.42bis implies the V.42 error checking protocol.
References in periodicals archive
The modem compression standards used on Fleet F33 are V44 and V42bis
This gives modem connections to Gandalf's Xpressway Modem Resource Module (MRM) up to a 50 percent performance improvement when compared to standard V42bis
running on most commmercially available modems.