Section: 19.10 Presence Reporting Area Identifier (PRA ID)
Content: The Presence Reporting Area Identifier (PRA ID) is used to identify a Presence Reporting Area (PRA). PRAs can be used for reporting changes of UE presence in a PRA, e.g. for policy control or charging decisions. See 3GPP TS 23.401[ General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access ]  [72], 3GPP TS 23.060[ General Packet Radio Service (GPRS); Service description; Stage 2 ]  [3] and 3GPP TS 23.203[ Policy and charging control architecture ]  [107]. A PRA is composed of a short list of TAs/RAs, or eNBs and/or cells/SAs in a PLMN. A PRA can be: - either a "UE-dedicated PRA", defined in the subscriber profile; - or a "Core Network predefined PRA", pre-configured in MME/S4-SGSN. PRA IDs used to identify "Core Network predefined PRAs" shall not be used for identifying "UE-dedicated PRAs". The same PRA ID may be used for different UEs to identify different "UE-dedicated PRAs", i.e. PRA IDs may overlap between different UEs, while identifying different "UE-dedicated PRAs". The PRA ID shall be encoded as an integer on 3 octets. The most significant bit of the PRA ID shall be set to 0 for UE-dedicated PRA and shall be to 1 for Core Network predefined PRA.