A standard for 56-Kbps modems
approved by the International Telecommunication Union (ITU)
in February, 1998. The V.90 standard resolves the battle between the two competing 56 Kbps technologies — X2
from Rockwell Semiconductor. Both manufacturers have announced that their future modems will conform to V.90. In addition, most users who already purchased 56 Kbps modems will be able to apply a software upgrade to make their modems support V.90.
Also see Dial-Up Modem Standards in the Quick Reference section of Webopedia.