Making A Bundled Call With X.75 - ZyXEL Communications omni TA128 User Manual

For European ISDN (DSS1), the Low-Layer-Compatibility (LLC)
information element in the SETUP message can be used to specify
the layer 3 protocol. Since this is an option for ISDN switches,
some of the switches might not deliver the LLC information
element to the remote end. There is no provision for 1TR6 switch
to specify the layer 3 protocol for X.75 calls.

Making a Bundled Call with X.75

A bundle connection is initiated at the calling site by sending two
consecutive SETUP messages to the network. The two SETUP
messages are all the same except for the Call Reference values.
AT&Jn can be used for bundle configuration as follows:
AT&J0 - Disables B channel bundling.
AT&J1 - Enables B channel bundling in answer mode only.
AT&J2 - Enables B channel bundling in call mode only.
AT&J3 - Enables B channel bundling in both call and answer
modes.
The bundle protocol can be selected as follows:
ATS100=0 - MLP channel bundling.
ATS100=1 - CCB channel bundling.
If channel bundling is enabled, the ATDIs command will generate
two consecutive SETUP messages to invoke bundle initiation.
For Northern Telecom ISDN, each BRI destination phone number
can only be called once in any time. In order to use two B channels
for aggregation, we must place two calls with different phone
numbers. The following command can be used for this purpose:
ATDIphone_number_1+phone_number_2
If the called site receives two consecutive SETUP messages with
the same Calling Party Number and Bearer Capability (or
Origination Address for and Service Indicator for 1TR6) then it
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