Place call to DISA facility of the system. 2. At receipt of Intercom dial tone/AA announcement, dial as desired. If DND Warning tone is received, enter an Authorization Code, to receive Intercom dial tone. Conditions 1. Each CO/IP path is separately assigned for DISA operation during Day, Night and/or Timed system operation mode. DISA operation is active only when the system is in the assigned operating mode(s). 2. DISA callers can be routed to a VMIM/VSF Auto Attendant announcement in place of Intercom dial tone. The announcement can be associated with a CCR Table or assigned to disconnect after playback (‘#’). 3. A DISA caller can be required to enter an Authorization Code to access the system’s external outgoing resources, facilities or features. If required, the caller is permitted to retry entry of a valid Authorization Code based on the DISA Retry count. Continued failure results in disconnect. 4. DISA callers are subject to COS dialing restrictions. If Authorization Codes are required and the code entered matches a Station Authorization Code, the station’s COS will apply. Otherwise, the assigned DISA COS will apply. In both cases, the CO/IP COS for the outgoing path will be active. 5. The system will disconnect an outgoing DISA call if the Unsupervised Conference timer expires or disconnect supervision is received. A disconnect warning tone is provided 15 seconds prior to disconnect. 6. If a DISA caller encounters a system All Lines Busy, busy tone is received for 5 seconds before ICM Dial tone is again presented and the DISA caller may try another call. 7. LEDs associated with the DISA CO Line appearance will provide normal status indications at all stations except the Attendants. The LED for the line at an Attendant will flutter at 240 ipm when busy. 8. An iPECS Phone user can only receive a DISA call with an available CO/IP appearance button.