V.90 Technology Frequently Asked Questions
This section provides answers to the most frequently asked questions
about V.90 technology.
1. How do I check my modem's current code date?
Using a terminal program (such as BVRP, HyperTerminal, MacComCenter,
ZTerm, and so forth.), type ATI7 and press the ENTER key.
There will be a line that says FLASH, EPROM, or SUPVISOR date. This is
your modem's code date.
2. How do I know if V.90 is enabled in my modem?
Open up a terminal software package, type ATI7 and press
the ENTER key while in terminal mode. This command displays the
modem's configuration profile information. If V.90 is enabled, V.90 will
be listed on the options line.
3. I have a V.90 modem and I'd like to know where I can
connect at V.90 speeds.
Contact your local ISP regarding V90 support. The USRobotics
BBS at (847) 330-4569 supports V.90 connections. Once connected, you will see a log on prompt. Enter +++, then enter ATI6. Click Enter. Your connect speed will be shown next to Speed. Entering ATH will disconnect the modem.
4. I have an V.90 modem which I am using to call into
an ISP which supports V.90, yet I'm not connecting at V.90.
Our research shows that the vast majority of telephone lines in
North America support V.90 connections. However, due to unusual telephone
line configurations, some users will not be able to take advantage of
It's important to remember that your line conditions may change, so
you may be able to make V.90 connections in the future.
To make sure that you can achieve V.90 speeds, perform the following
- First, make sure your modem supports V.90. You can verify that your
modem supports V.90 by opening a terminal application (BVRP, HyperTerminal,
MacComCenter, ZTerm, and so fourth.) typing ATI7, and pressing
the ENTER key. If the Options line has V.90 listed, then your
modem supports V.90.
- Make sure that the number you're dialing into is an actual V.90 server.
Some ISPs may have a mixture of V.90 and non-V.90 servers. You can check
this by contacting your ISP/Online Service and asking them about V.90
- If it is a V.90 server, you may want to try calling it a few more
times. Remember, the phone company routes each call in a different fashion.
- If you've called into the V.90 server multiple times and never connected
at V.90, you may want to call a different V.90 number. The USRobotics
BBS at (847) 330-2780 has V.90 servers attached to it.
- If you connect at V.90 on the USRobotics BBS, there may be something
between you and your ISP that is preventing a V.90 connection from being
negotiated. You may want to contact your ISP and see if they have received
similar reports from other customers.
- If you do not make a V.90 connection to our BBS, your line might
not be capable of supporting V.90. If that's the case, then see the
next item in this list.
- If you are experiencing consistent problems with V.90 connections
(such as not making a V.90 connection, abrupt disconnections, and so
forth), you can do one of two things. First, you can take a look at
the V.90 Requirements - Technical Details
section below and see if something in your line configuration will prevent
V.90. Or, you can call USRobotics Technical Support for USRobotics
modems at (801) 401-1141. Before you contact support, please dial into
the USRobotics BBS or another V.90 server with a terminal program
(BVRP, HyperTerminal, MacComCenter, ZTerm, and so forth), wait one minute
then type +++. When the modem responds OK type ATI4I6I7I11Y11
and then press the ENTER key. Now, type ATH and press
the ENTER key to hang up. Keep all this information available
when you contact our support department.
5. I make a V.90 connection, but it's not at 56K. Why?
FCC regulation prevents all devices attached to the telephone network
from exceeding a certain power output. As a result, we had to scale back
the output, which has a direct effect on the speed at which we can transfer
data. Currently, we have the server modem limit set to 53333. This does
not mean that people will not be able to hit the higher speeds, it just
decreases the likelihood.
Also, there are many factors which can influence the connection rate
and the speed at which you transfer data. Even though one end of the connection
is pure digital, there are things that can hamper an V.90 connection,
while not necessarily preventing it all together. Essentially, the characteristics
of the phone line play an essential role in the speed of the connection.
6. Where can I find more information on V.90?
Information is available on our Web site at: http://www.v90.com
V.90 Requirements - Technical Details:
V.90 is a new technology that utilizes the telephone system in a way
that has never been tried before. However, as a result, it has some requirements
that were unnecessary in previous speed technologies.
There are three primary requirements for V.90 speeds to be achieved.
- Digital at one end. This end is where the V.90 server lies.
The digital line servicing the V.90 server must be an ISDN PRI, ISDN
BRI or a "trunk-side" T1. Confirming that your ISP/Online
Service supports V.90 will be good enough to verify that this requirement
- V.90 support at both ends. In order to achieve V.90 speeds,
both ends of the connection must support V.90. In other words, you must
have a V.90 modem (called a V.90 client) on your end and your ISP/Online
Service must have a V.90 device on their end (called a V.90 server).
To check for V.90 support on the server side, talk to your ISP/Online
service about V.90 availability.
- One analog section. This is the section most relevant to you.
In almost all residential homes, the phone line going into your modem
or phone is analog. This does not mean that it is all analog to the
CO (Central Office), which is a very important aspect.
After determining that your line is capable of V.90 connections, there
are other items which can hamper V.90 connections, either by reducing
the capacity of the modem to attain higher speeds or by reducing the number
of times you actually achieve an V.90 connection. Some important factors
||These are found primarily in long wire lengths to improve the quality
of a voice call. They will not necessarily prevent V.90, but they
can reduce the speed of your V.90 connects.
||These come in primarily two forms: digital and analog. Both types
are used to balance the volume between different lines, so that the
volume of the voice call is the same on both ends and within a reasonable
range. With a digital pad, the digital data is manipulated to adjust
the volume. There may be a reduction in V.90 speeds with this, but
it should not prevent V.90 connections. With analog pads, the digital
data is converted to analog where the volume is adjusted and then
converted back to digital. This will prevent an V.90 connection since
there is more than one analog section in the path.
||In the home or in the phone company's area, wiring can also hinder
V.90 connections or speeds. If the lines are old and/or subject to
a lot of interference that may reduce your V.90 speeds.