Advanced Isdn Call Control; Call Control For Dss1 (Digital Subscriber Signaling #1); Control Of Outgoing Service Indicator - ZyXEL Communications Omni TA128 User Manual

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Advanced ISDN Call
Control
Call Control for DSS1 (Digital Subscriber
Signaling #1)
In order to initiate a DSS1 ISDN call, two information elements are
necessary:
• Bearer Capability - indicates what kind of bearer service is
desired. It is also used for compatibility checking in the addressed
entity.
• Called Party Number - provides necessary information for the
telephone company Central Office (CO) to direct the call to the
destination.
Other optional information elements which are pertinent to call
control include:
• High-Layer-Compatibility.
• Low-Layer-Compatibility.
• Calling-Party-Number.
• Called-Party-Number.
• Calling-Party-SubAddress.
• Called-Party-SubAddress.

Control of Outgoing Service Indicator

The High-Layer-Compatibility and Low-Layer-Compatibility
information provides a means for compatibility checking by the called
party. They are transferred transparently by the ISDN network
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