Dialogic 6.2 Manuale Utente

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Wink Start & Delay Dial Signaling
November 2009
276
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 
 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