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?

Answer:
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?

Answer:
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.

Answer:
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.

Answer:
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 this technology.

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 tests:

  • 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 availability.
  • 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?

Answer:
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?

Answer:
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. They are:

  1. 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 is met.
  2. 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.
  3. 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 include:

Item Description
Load coils 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.
Pads 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.
Wiring 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.