Dialogic 6.2 Immediate Start/Fixed Pause Signaling, Incoming Call Processing Immediate Start

Immediate Start/Fixed Pause Signaling

Immediate Start/Fixed Pause Signaling

Immediate Start signaling applies to incoming calls only; Fixed Pause signaling applies to outgoing calls only. Since these signaling types functionally complement each other, they are handled together by Brooktrout modules. The exact protocol to be used for a call is automatically selected depending on whether an incoming or outgoing call is being handled. To avoid confusion, the symbolic constants used to select these two protocols, IISDNttIMMEDIATE_ DIAL and IISDNttFIXED_PAUSE, are set to the same value.

To configure a Brooktrout module for immediate start and fixed pause mode signaling, the host must issue an L4L3mENABLE_CAS with an IISDN_ROBBED_BIT_DATA structure that contains the following settings:

„send_glare_err_event = 0 (not used)

„in_trunk_type = IISDNttIMMEDIATE_DIAL or IISDNttFIXED_PAUSE

„out_trunk_type = IISDNttIMMEDIATE_DIAL or IISDNttFIXED_PAUSE

„fgb_fgd_mode = 0 (not used)

The remaining settings are described in the context of incoming and outgoing calls in the subsections that follow.

Incoming Call Processing (Immediate Start)

During an incoming call, the host receives an L3L4mPRE_SEIZE message if send_preseize_event = 1 in the IISDN_ROBBED_BIT_ DATA structure. This message is sent when the module detects an incoming seizure (off hook). The module then collects dial pulse digits from the network; the maximum number of digits the module expects to receive must be specified in the max_incoming_digit_ count field. The digits are reported to the host in an L3L4mSETUP_ IND message. To answer the call, the host must issue an L4L3mCONNECT_REQUEST message.

Figure 29 shows how a Brooktrout module processes an incoming call received over an immediate start trunk.

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