Abstract: A variety of methods and systems can be used to avoid a hairpin loop scenario. For example, in a system involving a redirecting switch and a service platform switch, correlation between calling party identities for outgoing and incoming call legs can be done to identify a potential hairpin loop scenario. Upon detection of such a scenario, appropriate call legs can be released while routing the call to its destination. Correlation information can be collected from available call setup signaling parameters. The methods and systems can be applied, for example, to systems involving directory assistance call completion, voice-activated dialing, voicemail callback, and prepaid services.

Abstract: A variety of methods and systems can be used to achieve electronic surveillance when a call is directed to a destination as a result of service processing. For example, in a system involving a redirecting switch and a service platform switch, correlation between calling party identities for outgoing and incoming call legs can be done to identify a hairpin loop scenario. Upon detection of such a scenario, an appropriate electronic surveillance message can be sent to a monitoring device indicating the call's destination. Correlation information can be collected from available call setup signaling parameters. The methods and systems can be applied, for example, to systems involving directory assistance call completion, voice-activated dialing, voicemail callback, and prepaid services.