Mass calling event detection and control

Abstract

A method for handling congestion in a communication network, known as a focussed mass calling event (MCE), occurring when the rate of calls to any given terminating number increases dramatically resulting in a large number of incomplete calls directed towards that number, known as ineffective attempts. Switches in the network operate under control of a network processor and ineffective attempts are logged and monitored by the switches. If the number of ineffective attempts on a switch for a particular terminating number exceeds a threshold in a given sampling interval, an MCE is detected on the switch and reported to the network processor along with the terminating number. The network processor responds by periodically broadcasting a gap control message to all the switches of the network identifying the congested terminating number and a gap time. The switches respond to the gap control message by placing a guard-time between calls to the particular terminating number based on the gap time. The switches also periodically report on the number of blocked and passed calls to the MCE terminating number which information is used by the network processor to adjust the gap time in the gap control message. This process continues until the congestion at the terminating number is alleviated.