3Com 3C421600A, Management Manual

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146 C
HAPTER
10: A
DVANCED
M
ODEM
C
ONFIGURATION WITH
CLI/AT
COMMANDS
The possible reasons for disconnect are explained in Table 40.
Table 40 Disconnect Reasons
.
Disconnect Reason Indication
Keypress Abort The modem detected a keypress while training.
Escape code The operator sent the modem the (+++) escape code.
GSTN (General Switch
Telephone Network)
Clear Down The connection was a non-ARQ and DTR was dropped
from one side of the connection, or the DISC frame was
corrupted due to noise.
Loss of Carrier The modem detected loss of the remote modem's carrier
and waited the duration specified in S10 (default is 0.7
seconds).
Inactivity Timeout The modem detected no activity on the line for the
duration specified in S19.Default is 0, timer disabled.
MNP Incompatibility The modem is set to &M5 and the remote modem does not
have MNP capability, or there was an MNP negotiation
procedure error.
Retransmit limit The modem(s) reached the maximum of twelve attempts to
transfer a data frame without error.
LD received The remote modem sent an MNP error control Link
Disconnect request.
DISC The remote modem sent a V.42 Disconnect frame.
Loop loss disconnect The modem detected a loss of current on the loop
connecting it with the telephone company central office
(CO). This usually occurs because the remote modem has
hung up: the CO drops current momentarily when there is
a disconnect at the other end of the call. Unless S38 is set
higher than zero, the modem immediately hangs up at
loop loss.
Unable to Retrain After several attempts, disturbances on the phone line
prevented the modems from retraining, and they could no
longer transmit or receive data.
Invalid speed The modem is set to &N1 or higher, for a fixed link rate,
and the remote modem is not operating at the same rate.
XID Timeout: The modems failed to negotiate the V.42 Detection (XID
Exchange) phase.
SABME Timeout (Set
Asynchronous Balance
Mode Extended) The modems failed this part of V.42 link negotiation.
Break Timeout Incompatible processing of a Break signal occurred.
Invalid Codeword The modem received an invalid V.42 bis frame.
A Rootless Tree The modem received an invalid V.42 bis .