High Probability of Completion (HPC) features comprise a set of functionalities that provide an enhanced probability of call completion to authorized Government Emergency Telecommunications Service (GETS) and Wireless Priority Service (WPS) users during network stress and/or congestion.

There are two methods in HPC call classification:

  • Early HPC classification—An HPC call is recognized based on the received SIP RPH content in the incoming INVITE or the code point in Calling Party's Category (CPC) parameter of the ISUP-MIME. For ANSI, the CPC parameter is National Security/Emergency Preparedness (NS/EP) and for ITU, the CPC parameter is International Emergency Preference Scheme (IEPS).
  • Late HPC classification—An HPC call can also be recognized by the PSX during analysis of the Called Party Number.

The SBC must be configured to use the external PSX for this feature. For more information on using the PSX for GETS / WPS, refer to the PSX documentation Government Emergency Telecommunications Service.

HPC capable switches such as GSX9000 enable HPC calls to receive additional network support to increase the chances of successful call completion.

For more information on GSX9000’s GETS and WPS feature, refer to GSX documentation Support for Government Emergency Telecommunications Service and Wireless Priority Service.

The  supports a subset of GSX9000's HPC capabilities and the capabilities are as follows:

  • Early or late HPC call classification
  • Call Admission Control (CAC) treatment: ingress CAC for early HPC classified calls and egress CAC treatment for early and late HPC classified calls
  • Resource-Priority header (RPH) which is used for treating and marking SIP calls as HPC calls.
  • Network Wide HPC (NW-HPC) License enforcement

The Service profile, hpcCallProfile, is configurable to classify a call as HPC and add RPH for HPC calls. Also, the parameter hpcOversubscription can be added to various CAC configuration objects to support the HPC CAC logic.

Preferential servicing of HPC calls is conditional on the installation of NW-HPC license on the EMS. For more information on EMS licenses, refer to the EMS documentation Licensed Applications and Features.

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