Hardware Reference
In-Depth Information
Inmid-2000,theITUunveiledamultifaceted solutiontotheproblemofslowconnections
and uploads: the V.92 and V.44 protocols (V.92 was previously referred to as V.90 Plus).
Most modems manufactured since mid-2001 to the present are V.92 compatible.
V.92, as the name implies, is a successor to the V.90 protocol, and any modem that sup-
ports V.92 also supports V.90. V.92 doesn't increase the download speed beyond the
56Kbps barrier but offers these major features:
•
QuickConnect
—QuickConnectcutstheamountoftimeneededtomakeaconnection
bystoringtelephone-linecharacteristicsandusingthestoredinformationwheneverthe
same phone line is used again. For users who connect to the Internet more than once
from the same location, the amount of time the modem beeps and buzzes to make the
connectionwilldropfromasmuchas27secondstoabouthalfthattime.Bearinmind,
though, that this reduction in connection time does not come about until after the ini-
tial connection at that location is made and its characteristics are stored for future use.
•
Modem-on-Hold
—The Modem-on-Hold feature allows the user to pick up incoming
callsandtalkforalongeramountoftimethanthefewsecondsallowedbycurrentpro-
prietary call-waiting modems. Modem-on-Hold enables the ISP to control how long
you can take a voice call while online without interrupting the modem connection; the
minimum amount of time supported is 10 seconds, but longer amounts of time (up
to unlimited!) are also supported by this feature. Modem-on-Hold also allows you to
make an outgoing call without hanging up the modem connection. Modem-on-Hold,
similar to previous proprietary solutions, requires that you have the call-waiting fea-
tureenabledonyourtelephonelineandalsorequiresthatyourISPsupportthisfeature
of V.92.
Note
Although Modem-on-Hold is good for the Internet user with only one phone line (because it
allows a single line to handle incoming as well as outgoing calls), it's not as good for ISPs
because when you place your Internet connection on hold, the ISP's modem is not capable
of taking other calls. ISPs that support Modem-on-Hold might need to add more modems to
maintain their quality of service if this feature is enabled. More modems are necessary be-
cause the ISP won't be able to count on users dropping their Internet connections to make or
receive voice calls when Modem-on-Hold is available.
•
PCM Upstream
—PCM Upstream breaks the 33.6Kbps upload barrier, boosting up-
loadspeedtoamaximumof48Kbps.Unfortunately,becauseofpowerissues,enabling
PCM Upstream can reduce your downstream (download) speed by 1.3Kbps-2.7Kbps
or more. PCM Upstream is an optional feature of V.92, and ISPs who support V.92
connections might not support this feature.
