System and method for monitoring the volume of calls carried by a voice over internet protocol telephone system

Abstract

A method and a system for controlling the load of calls carried by a voice over Internet protocol telephone system attempts to reduce or eliminate the overloading of individual trunk groups and/or destination gateways. The system obtains information relating to a plurality of calls in the system, and analyzes the call information to determine if certain trunk groups or destination gateways are overloaded. If so, the system issues commands so that additional calls are diverted away from the overloaded trunk group or destination gateway.

What is claimed is: 
     
         1 . A method of controlling the load of calls carried by a voice over Internet protocol telephone system, comprising:
 experimentally determining a first destination gateway's call carrying capacity by sending calls through the first destination gateway after it has been placed in service, wherein the call carrying capacity includes the number of calls that can be simultaneously handled by the first destination gateway;   obtaining, with a controller, call information relating to a plurality of calls that are presently being carried by the voice over Internet protocol telephone system, wherein the obtaining step comprises determining the number of calls presently being carried by the first destination gateway that are in a connected or setup state;   analyzing the obtained information to determine if the first destination gateway is at or near its experimentally determined call carrying capacity; and   controlling the routing of additional new calls before they are connected to the first destination gateway, such that at least some new calls are routed to destination gateways other than the first destination gateway to reduce the call load on the first destination gateway when the first destination gateway is determined to be at or near its experimentally determined call carrying capacity.   
     
     
         2 . The method of  claim 1 , wherein the controlling step comprises causing additional new calls that could have been completed through the first destination gateway to be completed through destination gateways other than the first destination gateway for a predetermined period of time. 
     
     
         3 . The method of  claim 1 , wherein the obtaining step comprises obtaining information about call traffic for a plurality of individual destination gateways, and wherein the analyzing and controlling steps are performed for the plurality of individual destination gateways. 
     
     
         4 . The method of  claim 1 , wherein when the analyzing step indicates that the first destination gateway is nearing its call carrying capacity, a new call admission rate that is indicative of the number of new calls that are completed through the first destination gateway per unit of time is kept below a predetermined threshold level. 
     
     
         5 . The method of  claim 1 , wherein the obtaining step comprises obtaining call information relating to a plurality of calls that are presently being carried by a subset of all of the destination gateways that can be used by the system to complete telephone calls. 
     
     
         6 . The method of  claim 5 , wherein the subset of all of the destination gateways comprises only those destination gateways that typically become overloaded. 
     
     
         7 . The method of  claim 1 , wherein the step of experimentally determining the first destination gateway's call carrying capacity comprises statistically analyzing call data for calls routed through the first destination gateway. 
     
     
         8 . The method of  claim 1 , wherein when the analyzing step indicates that the first destination gateway, which provides high call quality, is at or near its call carrying capacity, the controlling step comprises causing additional new calls that could have been completed through the first destination gateway and that do not require high call quality to be completed through destination gateways other than the first destination gateway for a predetermined period of time. 
     
     
         9 . The method of  claim 1 , wherein when the analyzing step indicates that the first destination gateway, which can complete calls for a low cost, is at or near its call carrying capacity, the controlling step comprises causing some new additional calls that could have been completed through the first destination gateway and that do not have to be completed for a low cost to be completed through destination gateways other than the first destination gateway for a predetermined period of time. 
     
     
         10 . A system for balancing the call load of a voice over Internet protocol telephone system, comprising:
 a call capacity determining unit that experimentally determines a first destination gateway's call carrying capacity by sending calls through the first destination gateway after it has been placed in service;   a data analyzing unit that obtains call information relating to a plurality of calls carried by the voice over Internet protocol telephone system, the call information indicating the number of calls carried by at least the first destination gateway that are in the connected or setup state, and wherein the data analyzing unit also determines if the first destination gateway is at or near its experimentally determined call carrying capacity; and   a load balancing unit that reduces a load carried by the first destination gateway if the data analyzing unit determines that the first destination gateway is at or near its experimentally determined call carrying capacity by causing at least some new additional calls to be connected through other destination gateways that are not at or near their call carrying capacity.   
     
     
         11 . The system of  claim 10 , wherein the load balancing unit causes additional new calls that could have been completed through the first destination gateway to be completed through destination gateways other than the first destination gateway for a predetermined period of time. 
     
     
         12 . The system of  claim 10 , wherein the data analyzing unit obtains information about call traffic for a plurality of individual destination gateways and determines whether the destination gateways are at or near their experimentally determined call carrying capacity, and wherein the load balancing unit reduces the load carried by those of the plurality of individual destination gateways that are at or near their experimentally determined call carrying capacity. 
     
     
         13 . The system of  claim 10 , wherein when the analyzing unit determines that the first destination gateway is nearing its call carrying capacity, the load balancing unit controls the admission of new calls to the first destination gateway such that a new call admission rate that is indicative of the number of new calls that are completed through the first destination gateway per unit of time is kept below a predetermined threshold level. 
     
     
         14 . The system of  claim 10 , wherein the analyzing unit obtains call information relating to a plurality of calls that are presently being carried by a subset of all of the destination gateways that can be used by the system to complete telephone calls. 
     
     
         15 . The system of  claim 14 , wherein the subset of all of the destination gateways comprises only those destination gateways that typically become overloaded. 
     
     
         16 . The system of  claim 10 , wherein the call capacity determining unit statistically analyzes call data for calls routed through the first destination gateway. 
     
     
         17 . The system of  claim 10 , wherein when the analyzing unit determines that the first destination gateway, which provides high call quality, is at or near its call carrying capacity, the load balancing unit causes additional new calls that could have been completed through the first destination gateway and that do not require high call quality to be completed through destination gateways other than the first destination gateway for a predetermined period of time. 
     
     
         18 . The system of  claim 10 , wherein when the analyzing unit determines that the first destination gateway, which can complete calls for a low cost, is at or near its call carrying capacity, the load balancing unit causes some new additional calls that could have been completed through the first destination gateway and that do not have to be completed for a low cost to be completed through destination gateways other than the first destination gateway for a predetermined period of time.