Selective Reject To Improve Performance On Noisy Lines; Synchronous Support For Mainframe Computers; Testing; V.everything - US Robotics Courier V.Everything Getting Started Manual

Selective Reject to Improve Performance on Noisy Lines

Selective Reject is an optional part of the ITU-T V.42 (LAPM) standard.
This feature improves performance on noisy lines by reducing the amount
of overhead incurred when the protocol must resend data due to errors.
When Selective Reject is active, only the frame that contained the error is
resent, instead of the frame plus all of the following unacknowledged
frames.

Synchronous Support for Mainframe Computers

The Courier can connect to synchronous serial ports to allow access to
mini computers and mainframe computers.

Testing

ITU-T V.54 loopback testing is available. The Courier can perform analog,
digital, and remote digital loopback tests to determine if there are
problems with the phone line, the remote device, or your Courier's
transmitter or receiver.

V.Everything

The Courier provides full support of the x2 (if enabled), V.34+, V.34
standard, V.Fast Class, V.32 terbo, and many other modulation schemes,
spanning the range of speeds between
300 bps and 56 kbps. We call this unique combination of abilities
V.Everything.
1-4 Courier V.Everything Getting Started Guide