OneContact Application Server - Notifier

This component purpose is to publish events to subscribers according to their subscriptions.



  • Allows an entity to subscribe on a list of events.
  • Receives events from any publisher, dispatching them to subscribed subscribers.
  • Events are ordered so that missing events are easily detected, therefore upon reception of new events, Notifier must order them to be delivered in the correct order.
  • The component logs information to the Performance Monitor related with the events (number of received events, missing events, time to dispatch an event and many others).
  • SNMP traps are sent by the component on any error processing the events.


 Relations to other modules

  • Notifier stores information about subscribers and their subscriptions in Provisioning or System databases, depending on if it’s an instance or system notification.
  • ServerManager, BaseService, OneSupervisor and OneAdmin components sends notifications towards Notifier.
  • Notifier sends notifications targeting ServerManager, BaseService, Statistics, ListManagement, CallControl, Timer, OneMediaCompressor, MonitoringService and to all component’s tracer.
  • All the components referred above subscribe in Notifier.
  • Integrations using OneContact’s SDK are allowed to subscribe in Notifier and receive notifications from it.
  • Notifier communicates with a SNMP Trap Receiver to send SNMP traps upon anomalous situations.




Performance & Scalability

  • Notifier scales vertically by adding CPU power and or memory.
  • CPU will increase accordingly to the number of simultaneous requests made to the component as well as the number of events being sent at the time.
  • Memory will increase accordingly to the number of subscribers, number of subscriptions, number of active event sequencers and number of events to be sent.



Failover cluster



  • Can be deployed in Intel x64 or AMD machines running Windows Server 2016.
  • Installed as a windows service.