Best-Effort Call Answering; Ambiguity Resolution Switch For Voice Calls; Multi Auto-Answering Of Data Calls - ZyXEL Communications Omni TA128 User Manual

Chapter 4 - ISDN Communication Basics
this number, Omni TA128 will attempt to use PPP protocol to handshake with remote no
matter what the setup message is coming from the switch indicates either a ISDN data call
or Speech (Voice) call.

Best-effort call answering

If some numbers have been set using &ZIn command (as can be seen by the AT&ZI?
command) and they are not matched with the address of the incoming call, the Omni
TA128 will, by default, ignore the call as it may be intended for other devices that share
the same S/T interface (S0 bus) with the TA128.
If you want the Omni TA128 to answer inbound calls using all possible protocols, you
can set the best-effort call answering bit as follows:
Command
ATS119.3=0
ATS119.3=1

Ambiguity resolution switch for voice calls

For a Speech or voice-band-data call, if the &ZI number assignment can tell which of the
analog adapters is being addressed, then the call will be delivered to the proper
destination. But sometimes, ambiguity of address matching may exist. This may happen if
the &ZIn numbers of the various protocols are either unassigned or not matched or the
address information is absent in the incoming SETUP message. In this case, users may
wish to set answering priority to an analog port. The AT&L n command sets the address
ambiguity resolution flag as follows.
AT&L0 The analog adapter 1 has the higher priority to answer a voice or voice-band-
analog-data call; if the analog adapter 1 is busy, the call will be routed to the analog
adapter, Phone 2.
AT&L1 The analog adapter 2 has the higher priority to answer a voice or voice-band-
analog-data call; if the analog adapter 2 is busy, the call will be routed to the analog
adapter, Phone 1.

Multi auto-answering of data calls

When an ISDN data call comes in, the Omni TA128 can determine the protocol to be
used in one of two exclusive ways.
1) By way of the information conveyed by the SETUP message (for DSS1, these
include the Bearer-Capability, Low-Layer-Compatibility, or High-Layer-
Compatibility information elements; for 1TR6, these include the Service Indicator as
well as an Additional Octet of the Service Indicator)
2) By the Multi Auto-answering process. The Omni TA128 determines the protocol by
monitoring the B channel signal sent by the calling site.
With either method, the data call can be identified by the Omni TA128 to be X.75,
V.110, V.120, or PPP, MPPP Async-to-Sync conversion.
Function
Answer call only when number matched (by default)
Best effort call answering
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