[Flowchart]
A DISA call from an outside party is received.
No
Is there a port available?
Yes
The PBX answers the call.
The OGM plays and the PBX starts to
receive the DTMF signaling.
Yes
The OGM stops.
No
Is a second digit dialed?
Is the first digit dialed?
Yes
Is the first dialed digit assigned a
destination for the DISA AA service?
The call is routed to the destination.
Yes
The PBX receives the dialed
digits and checks the dialed
number.
No
What is the DISA security mode?
Continued on next page

F

A

The call is routed to an operator,
etc. (DISA Intercept when All
DISA Ports are busy)
(DISA Mute & OGM Start Time
after Answering expires)
(DISA Delayed
Answer time expires)
(DISA Second Digit Time for
Automated Attendant expires)
No
What method is assigned for
DISA Intercept Routing No Dial?
Operator Disable AA-0, AA-9
The call is
disconnected.
The call is redirected to
the destination assigned
to AA-0 or AA-9.
The call is routed to an
operator.
(DISA First Digit Time
When No Dial expires)

C C

76 Feature Manual Document Version 2008-11

4.1.7 DISA (Direct Inward System Access)