Notes On X2 56K Modem Support - Bay Networks 5399 Release Note

Remote Access Software Version 5.3 Release Notes

Notes on x2 56K Modem Support

U.S. Robotics has set up a BBS where you can test your line for x2 support
by dialing 1-888-877-9248 from a terminal program and logging in as
LINE TEST. Refer to http://x2.usr.com/connectnow/linetest.html for
complete details. If your phone line meets the criteria of the line test, you
probably can use a 56K modem. Note, however, that a call to the U.S.
Robotics test line may be routed differently than a call to your own facility.
The only way to find out for certain if your line is compatible with x2 is
to borrow a 56K modem and dial in to your 5399 RAC or 8000 RAC from
your home or office.
The x2 protocol can be very optimistic in establishing a high speed
connection. This may result in a connection that, while reporting a high
connect speed, may actually underperform a V.34 connection. If this
happens, you might want to disable x2 in the client modem. Refer to your
modem manufacturer's documentation for the specific modem command
to do this.
300115-B Rev. A
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