Toshiba V.90, User Manual

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Some phone lines will not support V.90 56K connections at all,
either because of quality impairments or additional digital-to-
analog conversions (i.e., PBX systems). The modem uses the V.34
protocol for “upstream” data transmission, which supports
connection rates of up to 33,600 bits/second.
NOTE: 56K rates can be achieved only when one V.90 56K
modem communicates with a V.90 56K host modem (i.e., a
V.90 56K end-user client modem connects to a V.90 56K
ISP-site modem).
The Toshiba internal modem automatically selects the V.34
protocol if the remote modem lacks V.90 capabilities or if a
combination of network and/or phone line conditions prevent the
V.90 connection. In this case, the maximum connect rate will be
33,600 bits/second.
This section of the user’s guide describes features of the internal
modem.
Features
56K data
communication The internal modem uses the V.90 protocol to connect
at data rates of up to 53,000 bits per second (bps) to
other modems employing the V.90 protocol. For
connection to non-V.90 modems, the internal modem
uses the ITU standard V.34 protocol to connect at
rates of up to 33,600 bits per second. The internal
modem also supports all of the earlier, lower-speed
ITU/CCITT modem protocols.
Fax capability You can use the internal modem to transmit and
receive facsimiles at rates of up to 14,400 bps. The
internal modem supports Class 1 fax transmission.
Refer to the function charts in this chapter.