Notification system

In information technology, a notification system is a combination of software and hardware that provides a means of delivering a message to a set of recipients. It commonly shows activity related to an account. Such systems constitute an important aspect of modern Web applications.

For example, a notification system can send an e-mail announcing when a computer network will be down for a scheduled maintenance.

The complexity of the notification system may vary. Complicated notification systems are used by businesses to reach whenever necessary critical employees.Emergency notification systems may take advantage of modern information technologies. Governments use them to inform people of upcoming danger.

The criticality of an event might change before the event is finally resolved. Sometimes a small failure may trigger a chain of failures that can lead to events that require immediate attention. For example, an e-mail that fails to send is not a significant error, and may be classified as a warning. However, the original incident that noted the e-mail failure may spawn a ping of the mail server responsible for relaying the e-mails. If the ping fails, the event may be escalated to a severe level, to indicate that a more important issue requires resolution.

In the event of a fire, or any emergency that requires human intervention, notification systems can provide a way of accepting feedback. The feedback can be used to determine what tasks the system should perform. For example, a chief firefighter, when notified of a pending fire, must acknowledge that the truck is en route, thus eliminating the need for further notifications.

Somewhat related to real-time interaction, above, certain notifications may bear more importance than others (for example, a fire alert would be more important than a cafeteria menu notification). Such types of notification would need to override any existing notifications of a lower priority.

If a notification system cannot contact the intended party, often it is not sufficient to let the matter drop. In the previous example, the chief firefighter was informed of a pending fire. However, if the chief was assisting a tree-bound cat, the notification might not reach its target. Consequently the system must find another person to notify, typically by scanning a predefined roster.

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Wikipedia