Call back, 5 call, Back – Nokia 9290 User Manual
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Nokia 9290 Communicator
Nokia Mobile Phones
Setting Up Dial-In Service
Copyright Nokia Corporation 2001-2002. All rights reserved
.
Available connection speeds are:
Connection type
Remote modem type
1 time slot
2 time slots
3 time slots
Normal data call
Analog
Autobauding,
9600, 14400
Not available
Not available
ISDN V.110
9600 or 14400
Not available
Not available
ISDN V.120
9600 or 14400
Not available
Not available
High-speed data call
Analog
9600-14400
19200-28800
Not available
ISDN
V.110
9600-14400
19200-28800
28800-38400
ISDN
V.120
9600-14400
19200-28800
28800-43200
When HSCSD connections are used, the user may control how many time slots are used for the connection. Some
GSM operators may charge on a slot amount usage basis, while other GSM operators may implement a fixed charging
model for HSCSD calls. Please contact your network operator for HSCSD coverage and charging details.
Modem init string is empty by default, but any valid GSM AT command can be typed here (start the string with “at”).
AT strings are used to configure the internal modem of the Nokia
9290 Communicator. If you experience problems
when creating data calls, please contact your GSM network operator or Internet service provider, who may provide a
suitable configuration string for this setting.
2.3.5 Call Back
Today it is very important to have the best available security in Internet connections. One feature to increase security
in the Nokia
9290 Communicator is support for call back on a PPP link. The other advantage of the call back is to
control phone costs of mobile terminals.
When using call back in the Nokia
9290 Communicator, call back is requested during PPP negotiation. After
negotiating call back, the remote server should close the connection and call back within one minute (60 seconds)
using the same connection rate which was used to connected to the call back server.
There are three call back modes available:
•
IETF PPP callback with a server-specified number (type 0)
•
Microsoft Callback with a server-specified number
•
Microsoft Callback with a client-supplied number
Use call back is used to set call back feature on or off. If this is set to “Yes”, the callback will be negotiated during the
PPP link configuration phase.
Call back type contains three alternatives. The first two options (MS call back and IETF call back) will use server
number call back, meaning that the call back number is stored in a database on the remote server. The remote server
finds the correct call back number after the client has authenticated itself to the server.