ZyXEL Communications omni series user manual Multi auto-answering of data calls

AT&L0 - Analog adapter 1 has the higher priority to answer a voice or voice-band-analog-data call; if analog adapter 1 is busy, the call will be routed to analog adapter 2.

AT&L1 - Analog adapter 2 has the higher priority to answer a voice or voice-band-analog-data call; if analog adapter 2 is busy, the call will be routed to analog adapter 1.

Multi auto-answering of data calls

When an ISDN data call comes in, the TA can determine the protocol to be used in one of two 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 TA 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 TA to be X.75, V.110, V.120, or PPP, MPPP Async-to-Sync conversion.

If the address-matching process is again unable to tell which protocol to use, the TA will go into its “Multi Auto-answering Routine,” by examining the B channel data pattern and hence determine the protocol to use.

When alerted, the TA will send a RING message to the DTE in the following format:

RING

FM:17145522863 TO:17142630398

34 ISDN Communication Basics