56k standard ABCs

The 56k technology was a Modem technology that offered a faster solution for end users and SOHO. When originally introduced, two technologies emerged: X2, which was developed by UsRobotics, and KFlex, which was introduced by Lucent and Rockwell. Unfortunately, with competing standards this caused confusion and difficulties for end-users and the ISP (Internet service provider). For example, if an end-user had an X2 modem, but the ISP only had KFlex modems, the end-user would be unable to achieve the optimal performance.

  • 56k standard ABCs
  • V.90 standard history
  • Technical support

Because of this dilemma, a new V.90 standard was developed. This standard merged X2 and KFlex that allowed maximum performance and compatibility.

V.90 standard history

September 1996 - UsRobotics (3COM) submitted the first V.90 56k proposal to ITU. November 1996 - Lucent and Rockwell announce the KFlex standard. April 1997 - ITU called for special working party to determine a 56k standard. September 1997 - ITU met but did not reach consensus on several technical aspects. December 1997 - Compromise on spectral shaping and multiple conversions. 25 of 30 favorable votes were cast. February 1997 - Standard determination. September 1998 - Standard ratification expected. February 6, 1998 - V.90 becomes a standard after ITU comes to final agreement.

Technical support

  • Unable to connect at 56k.
  • How should I upgrade to V.90?
  • I upgraded to V.90 and now my modem does not work.

Unable to connect at 56k

If you’re connecting at or close to 53k or close to 53k, such as 41k or 42k, it’s the highest you’ll be able to connect. The FCC has a limitation of 53k, if you are not connecting at high 40k or low 50k speeds verify the below recommendations.

  • Verify your ISP uses the same standard that you are using. If your ISP only provides X2 technology, then you are only going to be able to connect at high speeds with an X2 modem. Today, this should no longer be a problem.
  • The 56k technology does not work over a digital line. Most homes use an analog line, but some offices and hotels use digital lines.

Finally, verify your ISP is not at fault and test the phone lines by trying a different ISP or another computer. With some phone systems and the distance to the central office, you may not be able to get 56k.

How should I upgrade to V.90?

Because of the variety of modem chipsets, we recommend you contact your computer or modem manufacturer to obtain complete information on upgrading your modem to V.90. Because this upgrade is a flash of a chip on the Modem card incorrectly can cause the modem to stop functioning.

I upgraded to V.90 and now my modem does not work

Unfortunately, this can be caused when downloading the incorrect V.90 modem update. Reinstall the modem and its drivers and then verify the V.90 update is correct. If you are not sure about the V.90 update contact either your computer or modem manufacturer for additional support and information.

  • Modem help and support.
  • List of modem manufacturers and links.
  • See our KFlex, Modem, V.90, and X2 definitions for further information and related links.