DCP Configuration
5-39
3910-A2-GN32-40
September 1998
Table 5-6
(1 of 7)
V.42/MNP/Buffer Configuration Options
Err Contrl Mode: V42/MNPorBfr
Nxt V42/MNPorBfr V42/MNPorDsc MNP_or_Buffr MNP_or_Disc BufferMode DirectMode
LAPM_or_Disc LAPM_or_Bufr
This configuration option is only available if Async/Sync Mode is configured for Async.
Error Control Mode. Determines the type of error control used by the modem. In most cases, V42/MNPorBfr
is the best choice. If V.42bis and MNP are enabled, then the modem uses the following priority for error
control negotiation: V.42bis, V.42, MNP 5 and below. Online changes do not take effect until a disconnect
occurs.
H
V.42/MNP or Buffer
Modem attempts to connect in V.42 Error Control mode using V.42 Link Access Procedure for
Modems (LAPM) protocol. If this fails, the modem attempts to connect in MNP mode. If this fails,
the modem connects in Buffer mode and continues operation. This is also known as V42/MNP
Autoreliable Mode.
H
V.42/MNP or Disconnect
Modem attempts to connect in V.42 Error Control mode using V.42 LAPM protocol. If this fails, the
modem attempts to connect in MNP mode. If this fails, the modem disconnects. This is also known
as Reliable mode.
H
MNP or Buffer
Modem attempts to connect in MNP mode. If this fails, the modem connects in Buffer mode. This is
also known as MNP Autoreliable Mode.
H
MNP or Disconnect
Modem attempts to connect in MNP mode. If this fails, the modem disconnects. This is also known
as Reliable mode.
H
Buffer Mode
Modem does not use error control and allows the DTE rate to differ from the communications line
rate. This mode should only be used if the DTE provides its own error control or if errors in data can
be tolerated. This setting is also known as Normal mode and is valid even if the remote modem is
set to Direct mode.
H
Direct Mode
Modem connects at a data rate equal to or less than the initial DTE interface rate. (The modem
never connects at a data rate greater than the initial DTE rate.) If the modem connects at a data
rate lower than the DTE rate, the DTE must then adjust its data rate to equal the modem rate.
Ultimately, the modem speed and DTE speed must be the same. Direct mode does not support
error control or data buffering.
H
LAPM or Disconnect
Modem attempts to connect in LAPM mode. If this fails, the modem disconnects.
H
LAPM or Buffer
Modem attempts to connect in LAPM mode. If this fails, the modem connects in Buffer mode.
NOTE: The modem must be reconfigured for Direct mode before changing the leased-line modulation if
V.42 error control or Buffer mode are enabled with V.32bis or TMp on leased lines.
