METHOD FOR DETECTING IMPROPER DELIVERY OF PARAMETERS, IN AN INITIAL ADDRESS MESSAGE, FROM AN INTERCONNECTING SWITCH

A method for detecting improper delivery of parameters in an initial address message (IAM), such as a calling party number (CPN), for calls set up to a switch over SS7 trunk groups connected to other carriers is described. When a call originates from a switch other than the local switch serving a caller ID customer, the CPN should be passed, as a parameter in a call setup message called an Initial Address Message (IAM), from the originating switch to any intermediate switches, and from those intermediate switches to the customer's terminating switch. The method allows a switch to reliably and proactively identify when an IAM parameter, such as CPN, is not being received (and should be), from an interconnecting switch, for calls over specific TSGs connecting two switches.