This Technical Report (TR) presents the results of the Feasibility Study on Priority Service. The intent of this Feasibility Study is to assess the ability of 3GPP specifications to meet high-level requirements identified for Priority Service. This Feasibility Study consisted of a multi-step process, namely:

1. Identify high-level requirements for Priority Service.
2. Determine existing relevant 3GPP specifications for Priority Service.
3. Perform a Gap Analysis to assess the ability of existing 3GPP specifications to meet the high-level Priority Service requirements.

As defined in this document, Priority Service allows qualified and authorized users to obtain priority access to the next available radio (voice or data traffic) channels on a priority basis before other PLMN users during situations when PLMN congestion is blocking call attempts. In addition, Priority Service supports priority call progression and call completion to support an "end-to-end" priority call. Priority Service is intended to be used by qualified and authorized users, i.e., emergency service personnel, only during times of emergency situations and network congestion. Access to Priority Service is limited to key personnel and those with leadership responsibilities and is not intended for use by all emergency service personnel. This is to ensure that non-emergency service personnel cannot "take over" the network and deny the other non-emergency service subscribers a reasonably level of service. Priority Service providers should adhere to uniform, nationwide operating access procedures. Priority Service can provide significant benefits for public safety. There may be times during emergencies when non-Priority Service subscribers will be unable to obtain access to their wireless services (because Priority Service personnel are using the channels); nevertheless, the benefits of Priority Service outweigh any inconvenience to non-Priority Service subscribers. Priority Service is to be available at all times in equipped markets in both the HPLMN and VPLMN within a country where the PLMN provider is offering the service. The capability for pre-emption should be supported, with the option to turn it on/off depending on regional requirements. Priority Service is applicable to both GERAN and UTRAN and is activated on a per call basis using Priority Service dialing procedures. Priority Service, supported by the 3GPP system set of services and features, is one element in ability to deliver calls of a high priority nature from mobile to mobile networks, mobile to fixed networks, and fixed to mobile networks.

This Technical Report (TR) presents the results of the Feasibility Study on Priority Service. The intent of this Feasibility Study is to assess the ability of 3GPP specifications to meet high-level requirements identified for Priority Service. This Feasibility Study consisted of a multi-step process, namely:

1. Identify high-level requirements for Priority Service.
2. Determine existing relevant 3GPP specifications for Priority Service.
3. Perform a Gap Analysis to assess the ability of existing 3GPP specifications to meet the high-level Priority Service requirements.

Additional functionalities not documented in this TR are considered outside the scope of this TR. Such additional functionality may be on a network-wide basis, nation-wide basis or particular to a group of users. Such additional functionality shall not compromise conformance to the requirements of the Priority Service defined in this specification. The Priority Service is intended to be utilised for both Voice and Data and therefore both elements are considered within the scope of this document. While Priority Service is meant for both Voice and Data services, the initial set of requirements address Circuit Switched Services (Voice as well as Data). Multimedia and non-circuit switched aspects of Priority Service have not been addressed in this feasibility study and are for further study. The Priority Service is intended to interwork with external networks to provide an end-to-end service. Therefore, service interactions with external networks are considered within the scope of this document, although the specification of these interactions may be in other standards. If this occurs, a reference to that specification shall be made.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

• References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.