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.