Frequently
Asked Questions---v.92 |
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What is V.92?
V.92 is a new proposed dial-up modem standard
that is being worked on by the International Telecommunications
Union (ITU). The proposed standard provides for
an increase in upload speeds, quicker connect
times and a modem-on-hold feature that allows
the modem to work in conjunction with call waiting
provided by the phone company.
- What V.92 offers:
Increased upstream rates - up to 48k by using
a PCM stream through an a/d conversion. [Still,
only 1 a/d conversion is required: if you have
trouble getting 56k rates with V.90, there will
be no improvement.]
Quick Connect - The time to establish a connection
may be reduced with faster handshaking.
Modem On Hold - Allows modems to stay connected
'on-hold' while you take an incoming call-waiting
call, or initiate an outgoing voice call. (Works
only if V.92 server modem is configured to allow
this feature.)
- More Info on Modem On Hold & V.92:
The amount of time you can place your Internet
connection on hold while taking another call will
be up to your ISP: the V.92 recommendation will
permit ISPs to set their modems to wait for 0 -
16 minutes, or, to wait indefinitely. V.92 client
modems may include software that will warn the user
when the ISP-determined timeout approaches, as well
as to display call-waiting caller-id info (requires
telco call-waiting/caller-id service). Note that
ISPs have an incentive to limit the use of this
feature: when a call is placed on hold, the ISP
modem remains unavailable to take other calls. The
ISP may need to add more modems to maintain quality
of service if this feature is enabled.
The V.92 specification will allow a PCM upstream
at rate from 24,000bps to 48,000bps. The rate will
increment in steps of 1.333k as in V.90. So, upstream
rates could be 24k, 25.3k, 26.6k, 28k, etc. While
the specification allows a 48k rate, it may be as
elusive as 56k with V.90.
V.92 modems will remember connect rates on past
connections by storing data about those connections
in a buffer. The modem will compare line quality
variables as it dials in to a server modem with
those in the buffer, and if a match is found, the
handshake starts at the rate previously negotiated.
Quick Connect will also be used with Modem On Hold:
when a call is switched back to the modem after
using the MOH feature, a retrain is required.
- Is there an increase in speed?
V.92 doesn’t increase the download speed over
V.90, but, it does increase the maximum upload speed
to 48K bps. This is a 30% increase over the 33.6K
bps attainable by today’s V.90 modems. This
higher upstream speed offers numerous benefits including
a reduction in the upstream data transfer time for
large e-mails with attachments and for ftp site
uploads, as well as improved operation for interactive
applications such as online gaming.
- What is the Quick Connect feature?
Quick connect dramatically improves how quickly
users can connect with their Internet Service Provider
(ISP). In some cases quick connect will approximately
halve the time required for a dial up modem to make
the "handshake" to an ISP on regularly
used connections, from approximately 20 seconds
with today’s widely deployed V.90 modems,
to less than 10 seconds with V.92-equipped modems.
- What is the modem-on-hold feature?
The modem-on-hold feature allows the modem to work
in conjunction with call waiting provided by the
phone company. The feature enables a PC user to
answer a new phone call for up to 16 minutes (or
for how long the Internet Service Provider permits)
– without dropping the modem connection. The
PC user is then able to resume surfing the Internet
after they terminate the voice call.
- What about other future developments
like V.44 compression?
Future developments, which will almost certainly
be incorporated in the first generation of V.92
modems, promise better download performance and
connection reliability. V.44 is a new data compression
standard that will improve the current V.42bis data
compression anywhere from 20 to 60 percent, up to
as much as 200 percent for certain types of highly
compressible data. The compression technique enables
data throughput rates of higher than 300K bps –
much faster than today’s typical rates of
150 – 200K bps. For users, it means that your
Web browsing will be much faster.
- Is there a market for V.92?
Today, many people still don’t have access
to broadband technologies such as DSL or cable modems.
According to recent GartnerGroup research, even
by 2004, 55% of all people will still be getting
to the Internet by way of a dial-up modem. V.92
provides a competitive analog modem solution in
the face of digital and cable connections. Faster
line negotiation and higher upstream data rates
in addition to more effective line usage through
call-waiting compatibility offer compelling adoption
benefits.
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