Toshiba V.92 - Manual (Page 100)

100 MNP and V.42
Data compression
5.375 x 8.375 ver 2.4.0
Modem port flow control
Modem port flow control refers to flow control between the
modems of the local station and remote station.
If data transmission from the modem under serial port flow
control is interrupted because the computer cannot catch up
with it, modem port flow control is applied to the remote
modem so that transmitted data will not exceed buffer
capacity. This flow control functions in normal mode only.
Data compression
Protocols MNP class 5 and V.42bis are included in the
modem to compress data received from the computer. The
receiving modem decompresses the received data and sends it
to its own computer. This data compression function
increases actual transmission speed up to twofold in
communications using MNP5 or up to three or fourfold in
communications using V.42bis. The compression ratio varies
depending on the data. Actual speed will not always be raised
close to the maximum compression ratio.
The V.44 compression standard provides more efficient data
compression than V.42bis, significantly increasing the
received throughput and reducing the download time for Web
pages.
Commands (%Cn)
Select whether or not to compress data in communications by
MNP class 5 or V.42bis as follows:
%C1 Enables data compression
For details, refer to “AT Commands” on page 51 .