The inherent nature of a paging system is that at any one time multiple audio sources can be competing for access to the same Zone. A priority scheme must be implemented to resolve conflicting demands on the system. The Vocia system of Priority Levels is configured by the system designer, who assigns a level of importance to every audio source in the system. This work is performed during system configuration (see Page Codes, Scheduler). Emergency Level Paging will always take precedence over regular Paging, however it follows the same Priority rules as discussed here.
The spin control box under the General tab of the Universe Properties allows a 'split' for the number of regular Paging Priority Levels vs Emergency Paging Priority Levels to be defined. The default Emergency Priority Threshold split is '101'. This means Paging Priorities 1 to 100 are available for non-Emergency Paging Priorities and 101 to 255 are for Emergency Paging Priorities. If this value was changed to '200', 199 non-Emergency paging Priorities and 56 Emergency Paging Priorities would be available.
Background sources in Vocia are automatically given the lowest Priority level and this cannot be changed. Only one background source can be sent to a particular Zone at any one time; however a background source can be sent to many different Zones at the same time. A Paging event at any Priority level takes priority over a background, by ‘ducking’ (lowering) the background volume during the event.
If a Zone is engaged by a Paging Event, and no other event is attempting to access that Zone, no conflicts will arise and the paging event will occur. If background audio is present in the Zone, it will duck according to the settings configured in the Ducker stage of the Zone’s output channels (see Ducker, VO-4 Audio & Live Control, VA-8600 DSP Live Control and VA-2030(e) and VA-4030(e) DSP Live Control). Once the paging event has been completed the background source will then resume at its original level.
However, if another paging event attempts to access the Zone while the first paging event is occurring or is about to occur a conflict resolution mechanism will be invoked. The outcome of this conflict will depend on the Priority Levels assigned to the Paging events. Listed below are the outcomes that are possible when two or more Paging events attempt to access the same Zone at the same time and a recommended Priority level scheme.
If this scenario occurs then the first Paging event will not be interrupted. What happens to the second Paging event depends on the type of Paging event it is.
If it is a Live Page and the Store & Forward function is enabled on the Paging device, the Page will be stored in the devices memory and placed in the queue for release later. See the Store & Forward section for further details. If the Store & Forward feature is not enabled, the second Page event will be discarded.
If it is a Recorded Announcement, again the Store & Forward functionality built into the system will store the message until the Zone has been cleared of Paging events of a higher Priority level. If it is a User Audio Input event, no immediate change to the routing of the Zone will take place. Once the Zone has been released by the first event and if no other Paging events are occurring in the Zone the User Audio Input event will be allowed to access the Zone. User Audio Input events are set up in the Scheduler, and are usually dependent on a time frame.
If this scenario occurs, the first Paging event will be interrupted. The higher level Paging event will automatically take control of the Zone and the lower Priority level event will be interrupted. Once the higher level Priority event has finished the Zone will be returned to any scheduled lower priority Paging event if one has been assigned to the Zone. Any continuing Live Page that was interrupted by the higher priority event will resume again. Pre-recorded Pages will not resume and will need to be actioned again.
It is recommended that Paging events be assigned Priority Levels according to the following guidelines. Please note that all regular Paging as shown below is assigned a lower Priority level than all Emergency Paging.