Policy Mid Call Actions are part of PSX call processing for the 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 GMSC solution, see the PSX Product Description document located at PSX Documentation.
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.
Policy Mid Call Actions are also used in PSX support for third-party application servers via XML- over-TCP, which involves the PSX SPAS (Sonus PSX/Application Server) service.
If the simulated call involves Policy Mid Call Actions, check Present for PolicyMidCall in SSReq. SSReq will wait for the Policy Mid Call. If SSReq receives the Policy Mid Call, SSReq displays it in the Policy Mid Call section and sends the subsequent Policy Request.
To simulate a Policy Mid Call Action using SSREQ, do the following:
If the call for which you have set up the corresponding policy request involves a Policy Mid Call Action, the response data will include sections for Policy Mid Call Data and Policy Mid Call Info.