Back to the Index page What is V.90?

V.90 is the official designator for the International Telecommunications Union's (ITU) draft recommendation for 56K modems. Known previously as V.pcm, the V.90 draft was approved in February 1998, clearing the way for universal compatibility among various 56K modems.

V.90 Technical Info
V.90 is a new technology that utilizes the telephone system in a way that has never been tried before. 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:
  1. Digital at one end, the end 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. This item is taken care of by the ISP/Online Service.

  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).

  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, but that does not mean that it is all analog to the Central Office.
After determining that your line is capable of V.90 connections, there are other issues that can hamper V.90 connections, either by reducing the speed capable or reducing the number of times that you actually achieve a V.90 connection. Some of these issues are: How do I Verify that My Phone Line Qualifies for V.90?
LineTest is a utility that U.S. Robotics has developed to test your line for x2 compatibility. Visit http://www.3com.com/56k/need4_56k/linetest.html for instructions on how to perform a LineTest. You may have an earlier version of LineTest on a Sportster 56K Connections CD. It is important that you use the latest test, as it is more reliable.
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