<protocol> 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 Not taken up as widely as K56flex and will shortly be superseded by the official V.90 standard.
(1998-09-08)
Try this search on Wikipedia, OneLook, Google
Nearby terms: X11R5 « X11R6 « X.12 « X2 » X.208 » X.209 » X.21