Boca Pro16 Series - Improving Performance with MNP 10

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BOCA PRO16 Reference Guide
F The PRO16RK modem supports eight special connect messages 20
to 28.
When the AT\V0 command is issued (default), your modem will
generate standard CONNECT messages for both normal and error-
corrected connections. If the X0 command has been issued, the CON-
NECT/REL will be the only ‘error correction’ response code generated,
regardless of the connection speed.
FIssue the %U1 command if you want your modem to issue CON-
NECT/LAP-M response codes when a V.42 connection is established.
The \V8 command will display details of the error correction and data
compression negotiated with the remote modem. This information is
displayed immediately before the CONNECT message.
The \V9 command will display details of the error correction and data
compression negotiated with the remote modem as well as diagnostic
information. This information is displayed immediately before the
CONNECT message.
Improving Performance with MNP 10
MNP 10 is neither an error correction or data compression technique.
MNP 10 works in conjunction with error correction and data compres-
sion to improve the performance of your modem when operating with
poor or varying quality telephone lines (as sometimes found with
overseas or cellular telephone connections).
With MNP 10 operating, your modem can automatically resize the MNP
packets, depending upon the line quality. When an MNP connection is
established, data is transferred in small ‘chunks’ known as packets.
When the line quality drops, MNP 10 reduces the size of packets being
transferred in order to maintain data throughput. MNP 10 will increase
the packet size to take advantage of improved line quality.
If the line quality becomes very good or very bad, MNP 10 can automati-
cally step between line speeds. MNP 10 attempts to use the highest speed
applicable to the quality of the telephone connection. If the telephone
line quality drops while you are connected to another MNP 10 modem,
thus introducing errors into your data, and the smallest packet size is
being used, the modems will ‘step-down’ in speed until the error rate
Error Correction
Error
Correction
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