A proprietary modem standard developed by US Robotics for 56 kbps communications. Not taken up as widely as K56flex and will shortly be superseded by the official V.90 standard.
Last updated: 1998-09-08
X-1 ♦ X11R4 ♦ X11R5 ♦ X11R6 ♦ X.12 ♦ X2 ♦ X.208 ♦ X.209 ♦ X.21 ♦ X.214 ♦ X.215
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