Is the correct 
PIN entered?
Does the caller press    
while hearing the reorder 
tone (Call Retry)?
Is the Walking COS/Verification 
Code Entry feature number dialled 
for Security Mode Override?
Yes
No
No
NoneNoneNoneNone All SecurityTrunk Security
Yes
Is the dialled number 
an extension number or 
floating extension number?
Yes
No
Extension No./
Floating 
Extension No.
What is the dialled number? 
Feature No.*
(Absent Message, 
FWD, etc.)
The feature is set. 
Trunk Access No.
+ Telephone  No.
Other
The dialled number is sent to the trunk.
Reorder tone 
Yes
No
A
B
B
C
C
D
D
No Security
The call is disconnected.
Continued from previous page
(DISA Reorder 
Tone time 
expires)
Yes
Is the extension 
in DND mode?
Yes
No
A
No
Yes
The call is established.
The call is routed to the 
intercept destination.
(DISA Intercept Routing  
No Answer)
Does the destination 
answer the call?
Does the 
destination 
answer 
the call?
No
Yes
The call is established.
The call is disconnected.
E
E
Does the caller press    
while hearing a ringback 
tone (Call Retry)?
The call is directed to the extension. 
The caller hears a ringback tone.
(DISA Disconnect 
Time after 
Intercept expires)
(DISA Intercept 
time expires)
G
* Feature numbers are available only when the Walking COS feature is used.
No
No
No
Is the extension 
busy?
Is Call Waiting
mode on?
Yes
Yes
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