ASAI and Call Control

For calls placed over ISDN-PRI facilities, if the ISDN ALERTing message is received from the network, the classifier is expected to detect the “in band” ringing and provide the “no answer” classification independent of receiving an ISDN ALERTing message.

For calls placed to on-ECS destinations, the “no answer” classification is done by counting the number of seconds of ringing.

The adjunct is notified of the no answer outcome in a Third Party Call Ended with cause CS3/19 — No Answer.

Busy Condition

For calls placed to off-ECS destinations, the busy results from the call classifier detecting either precise or imprecise busy tones or the “DISConnect/cause=user busy” (CS0/17 — User Busy) message returned by an ISDN-PRI facility.

A Third Party Call Ended is sent in these cases to the adjunct with cause value CS0/17 — User Busy.

For calls placed to on-ECS destinations, the busy condition is the result of the “busy” internal feedback message. Again, a Third Party Call Ended is sent to the adjunct with cause value CS0/17 — User Busy.

Reorder Condition

For calls placed to off-ECS destinations, the reorder condition is from the call classifier detecting either precise or imprecise network reorder tones, or receipt of an ISDN “progress” or “disconnect” message with cause CS3/42 — Denial/Reorder. A Third Party Call Ended is sent to the adjunct (cause CS3/42 — Denial/Reorder).

For calls placed to on-ECS destinations, the reorder classification is the result of the “reorder” internal treatment. A Third Party Call Ended is sent with the following cause: CS0/34 — No Circuit or Channel Available.

Other Conditions

When a Switch-Classified call is made to a destination that gives modem tone, the call is dropped (ended) with cause CS0/58 — Requested Bearer Capability not Available.

ECS-Terminated Call Conditions Prior to

Classification

Before a call is classified, some conditions will cause the ECS to terminate the call attempt:

No trunks available (none administered or none idle) (cause CS3/20 — Trunks not available)

Issue 7 May 1998 4-15

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Lucent Technologies 555-230-220 manual Busy Condition, Reorder Condition, Other Conditions