Flex System Hubs, Vault 20S, and Web Authorizers periodically contact CyberAudit-Web to report their status and fetch updates. By default that occurs once every 30 seconds. In addition, CyberAudit-Web attempts to notify a hub using TCP/IP on port 80 when it has an update for that hub. This "push notification" causes the hub to contact CyberAudit-Web immediately rather than wait for its normal check-in time. If desired, port 80 may be changed to another value on a hub-by-hub basis using the Push Notification Port setting in the hub properties page. The result of this notification is that online hubs can get instructions to update key, vault, and door records in nearly real time.
In cases where TCP/IP traffic is routed in both directions between CyberAudit-Web and the Flex System hub or Web Authorizer, push notifications will occur automatically. In some cases the hub may not be on the same network as CyberAudit-Web. An example of this is when CyberAudit-Web is being served on the Internet and the hub is behind a NAT router. The Push Notification Port enables the use of port forwarding on the router to direct those notifications to hubs in the local network.
