BinTec X4000, Руководство пользователя

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X4000 User’s Guide 329
Access Security
10
Callback offers the following selection options:
Table 10-8: Callback
Possible values Meaning
no X4000 does not call back.
expected (awaiting
callback)
X4000 calls the WAN partner to initiate
callback.
yes (PPP negotiation) X4000 calls back with the extension entered for
the WAN partner. If no number is entered, the
required number can be reported by the caller
in a PPP negotiation. This setting should be
avoided if possible for security reasons.
However, no alternative is currently available
for connecting Microsoft
➤➤
clients over data
transmission networks.
yes (delayed, CLID only)
X4000 calls back after approx. four seconds, if
requested to by the WAN partner.
yes (PPP negotiation,
callback optional) Corresponds to the value yes (PPP
negotiation), but contains an abort option.
The Microsoft client has the option of aborting
callback and maintaining the initial connection
to
X4000 without callback. This is done by
pressing CANCEL to close the dialog box that
appears.
Exception: This abort option cannot be used if
the WAN partner dialing in uses Windows NT
and his extension number is entered in
X4000 .
yes
X4000 calls back immediately, if requested to
by the WAN partner.
If yes (PPP negotiation) is used as the setting for
Callback
, a B-channel is
always opened, which results in costs.