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Policy Mid Call Actions are part of PSX call processing for the Sonus Gateway Mobile Switching Center (GMSC) solution. The PSX generates Policy Mid Call Actions during late call forwarding scenarios in mobile and AIN networks. For more information on the Sonus GMSC solution, see the PSX Product Description document located at the Sonus Documentation and Support Portal.
When call redirection occurs due to a late call forwarding event (such as a no-answer condition in which a call is then forwarded to the subscriber's voice mail), the Terminating VMSC (Visited Mobile Switching Center) sends the new redirection data (which includes the Forward To Number) to the PSX. The PSX in turn sends the new redirection data to the SBC in a Mid Call Action. The SBC adds the new redirection data to the currently stored data and passes the new data to the PSX in the subsequent policy request to route the call to the Forward To Number.
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