How Paging Works in CIC

Paging Services uses the carrier telephone number to select the appropriate carrier out of a list of known paging carriers. The list of carriers is configurable from Interaction Administrator and is maintained by Directory Services. The list is read at initialization and monitored by Paging Services for changes during operation. If a carrier is found in the list, Paging Services uses stored parameters to establish the connection with that carrier. Failure to find a matching carrier will cause the system to attempt to establish a connection anyway using common defaults in the hope that the page can be sent. An event is logged in this case even if the page is sent successfully to indicate that a new carrier should be added to the list in Directory Services.

To most efficiently use telephone lines, non-urgent pages are processed in batches by collecting page requests for a configurable interval, sorting them according to carrier, and then sending as many as possible during a single call to the carrier. There may be carrier-imposed limits as to how many pager messages may be transmitted in a single call, so the paging server will continue to make as many separate calls as are required to process all of the page requests.

Page requests that are specified as urgent are sent immediately.

Pages may also be scheduled for future transmission. Messages waiting for their send time to arrive are sorted by send time and carrier. If there are multiple messages to send to the same carrier at the same time, an attempt will be made to send them all during a single connection, subject to the carrier-imposed limitations on connection time and message length.

Scheduled messages whose send time has arrived take priority over batch messages. A batch transmission that is in progress will be allowed to complete, at which time all messages scheduled for the current time will be sent. Further processing of any pending batch messages can then resume.

Page requests whose send time is in the past (either because that is what was supplied by the user or because upon return to service following a failure it is discovered that scheduled messages have not been sent) are treated as urgent and sent immediately.

Unsent pager messages are stored on disk so that if the CIC system is unavailable for some period of time the messages are maintained and sending is resumed upon the system's return to service.