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 TS 23.401
, TS 23.060
and TS 23.203
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.
A Dedicated Core Network ID (DCN-ID) identifies a Dedicated Core Network (DCN) within a PLMN.
The allowed values of DCN-ID shall be in the range of 0 to 65535.
Values in the range of 0 to 127 are standardized and defined as follows:
0: Spare, for future use
127: Spare, for future use
Values in the range of 128 to 65535 are operator-specific.
The use of the standardized DCN-ID is specified in TS 23.401