Wink Start & Delay Dial Signaling

Wink Start & Delay Dial Signaling

In the Wink Start protocol, the device seizing the line expects a wink signal (a short-duration - 140 to 290ms - offhook signal) to be sent back as acknowledgment before sending the address digits.

In the Delay Dial, the device seizing the line expects an off-hook response from the far end for at lest 140ms, and waits for the far end to return to on-hook state before sending the address digits.

Although the protocols are different, the sequence of signals sent by both Wink Start and Delay Dial protocols is virtually identical, so these two protocols are often handled together.

Only two signaling bit patterns are used for these protocols. Pattern 00 (A and B bits zero) indicates the line is idle, while AB = 11 indicates a line seizure on the initiating end and the off-hook signal on the receiving end. Since the two bits must always have the same value, usually only the A bit is verified and the B bit ignored, thus eliminating the need to handle invalid bit patterns.

Wink start and delay dial trunks use almost identical signaling. To configure a Brooktrout module for standard wink start 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 for wink start)

„in_trunk_type = IISDNttWINK_START (the default value)

„out_trunk_type = IISDNttWINK_START (the default value)

„fgb_fgd_mode = 0 (refer to Wink Start with Feature Group B & D on page 281 for wink start with Feature Group B and D signaling)

To configure a Brooktrout module for delay dial 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 for wink start)

„in_trunk_type = IISDNttDELAY_DIAL

„out_trunk_type = IISDNttDELAY_DIAL

„fgb_fgd_mode = 0

November 2009

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Image 276
Dialogic 6.2 manual Wink Start & Delay Dial Signaling, November 276