0049-1800-xxx 326X V.34, V.34-SDC and V.32bis Series Modem – USER’S GUIDE 02/23/2010
Rev. A
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ITU V.13
V.13 signaling allows your modem to communicate with non-Raymar-Telenetics
modems. This signaling operates when the modem is configured for synchronous
mode.
ITU V.22 bis
2400 bps modem standard for use with dial and leased-line circuits.
ITU V.24
An electrical standard for interconnecting data communications equipment and
data terminal equipment established by the ITU. It is the most commonly used
computer/modem interface. Nearly equivalent to EIA/TIA 232-D.
ITU V.25 bis
An ITU-specified serial Auto-Call Unit (ACU) for operation with both
asynchronous and synchronous DTE equipment.
ITU V.32
The standard for 2-wire, full-duplex modems operating at up to 9600 bps for use
on the general switched telephone network and on leased telephone circuits.
ITU V.32 bis
A modulation standard that extends the speed of 2-wire leased line and 2-wire
dial line modems to include 14.4 and 12.0 kbps. It is backwards-compatible with
the V.32 modulation mode. When operating in the V.32 bis modulation mode,
the modem supports synchronous and asynchronous transmission rates of 4.8, 7.2,
9.6, 12.0, and 14.4 kbps.
ITU V.42
Used with full-duplex asynchronous data transmission, V.42 is an ITU-adopted
standard which specifies two methods of error correction for modems: MNP 4
and LAPM (Link Access Protocol for Modems).
ITU V.42 bis
Used with full-duplex asynchronous data transmission, V.42 bis is a high-
performance data compression algorithm based on the Lempel-Ziv Data
Compression algorithm. This compression technique is not compatible with MNP
5 or other MNP levels. The theoretical limit of V.42 bis is 4:1 compression. The
actual compression (throughout) that is achieved with any algorithm, including
V.42 bis is data (file) dependent. Using V.42 bis, the modem continuously
monitors the compressibility of user data. If user data is not compressible, the
V.42 bis algorithm detects this condition and automatically turns data
compression off, so the data link rate is never less than the modem modulation
rate.
ITU-TS V.34
V.34 is four-dimensional trellis-coded modulation standard using precoding and
pre-emphasis equalization schemes.
Interface
A shared connection or boundary between two devices or systems. The point
(logical or physical) at which two devices or systems are linked.
LAPM
Link Access Protocol for Modems. An ITU link layer protocol for modems.
