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The International Telegraphic Union (ITU), defines the standards.
The 'V.xx' is the spec number, the title is in bold, a description in plan text.
The term 'bis' refers to the 2nd version.
V.13: Simulated half-duplex (switched-carrier) control.
V.17: A 2-wire modem for facsimile applications with rates up to
14 400 bit/s
V.21: 300 bits per second duplex modem standardized for use in the
general switched telephone network
V.22: 1200 bits per second duplex modem standardized for use in
the general switched telephone network and on point-to-point 2-wire
leased telephone-type circuits: Synchronous/asynchronous data
transmission, full duplex over 2-wires, 1200bps.
V.22bis: 2400 bits per second duplex modem using the frequency
division technique standardized for use on the general switched telephone
network and on point-to-point 2-wire leased telephone-type circuits
V.26bis: 2400/1200 bits per second modem standardized for use in
the general switched telephone network
V.32: A family of 2-wire, duplex modems operating at data
signalling rates of up to 9600 bit/s for use on the general switched
telephone network and on leased telephone-type circuits:
Synchronous/asynchronous data transmission, full duplex over 2-wires,
9600bps (fall-back to 4800bps).
V.32bis: A duplex modem operating at data signalling rates of up
to 14 400 bit/s for use on the general switched telephone network and on
leased point-to-point 2-wire telephone-type circuits:
Synchronous/asynchronous data transmission, full duplex over 2-wires,
14.4kbps, 12kbps,9600bps, 7200bps, 4800bps.
V.33: Synchronous data transmission, full duplex over 4-wires,
14.4kbps, 12kbps.
V.34: Synchronous/asynchronous data transmission, full duplex over
2-wires (2/4 lines, leased), 28.8kbps.
V.34+: A modem operating at data signalling rates of up to 33 600
bit/s for use on the general switched telephone network and on leased
point-to-point 2-wire telephone-type circuits: Synchronous/asynchronous
data transmission, full duplex over 2-wires (2/4 lines, leased),
33.6kbps
V.90: A digital modem and analogue modem pair for use on the
Public Switched Telephone Network (PSTN) at data signalling rates of up
to 56 000 bit/s downstream and up to 33 600 bit/s upstream: (56K)
Synchronous/asynchronous data transmission, full duplex over 2-wires,
56kbps. The V90 uses Pulse Code Modulation (PCM).
V.91: A digital modem operating at data signalling rates of up to
64 000 bit/s for use on a 4-wire circuit switched connection and on
leased point-to-point 4-wire digital circuits
International Telegraphic Union (ITU), located at http://www.itu.int
Analog Devices
{V.35 xceviers}
Cermetek Microelectronics Inc.
{Modem Modules, Low Speed / High Speed Modems}
CML "Consumer Microcircuits Limited"
Linear Technology
{V.35}
PLX Technology
{serial bridges with UART, PCI, PCIe, Parallel/Local Bus and USB Interfaces}
TI
{High-speed QAM modem chip sets}
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Related Component Manufacturers;
TeleCom Device Manufacturers
Memory Chip Manufacturers
Processor Manufacturers
Glue Logic Manufacturers
Cable labs {Cable Modem Specifications}
Modem AT Commands {Jason John Schwarz}
RS232 Cables, Wiring, and pinouts
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