Content for  TS 33.128  Word version:  18.7.0

If the MME receives one or more cell IDs in an S1 message (as specified in TS 36.413), the POI associated with the MME shall report all of them. The IRI-POI in the MME shall only generate xIRI containing the MMEIdentifierAssociation record in the following scenarios:

• IdentifierAssociation: MMEIdentifierAssociation and Tracking Area/EPS Location Update (see clause 12.2.1.2 of TS 33.107) records shall be generated. No other record types shall be generated for that target.
• All: All MME record types shall be generated.

When Option A specified in clause 6.3.1 is used:

• The IRI-POI present in the MME shall send the xIRIs over LI_X2 for each of the events listed in clause 6.3.2.3 of TS 33.127, the details of which are described in the following clauses.
• In addition to the xIRI events listed in clause 6.3.2.3 of TS 33.127, the MME shall support xIRI generation in case of SMS over NAS as specified in clause 18.2.4 of TS 33.107. For records related to SMS over NAS in EPS:
  • The IRI-POI present in the MME shall set the payload format to EpsHI2Operations.EpsIRIContent (value 14), see clause 5.3 and ETSI TS 103 221-2 [8] clause 5.4. The payload field shall contain an EpsHI2Operations.EpsIRIContent structure encoded according to clauses 10.5, 15.2 and B.9 of TS 33.108.
  • As the LIID may be not available at the MME but is mandatory in EpsHI2Operations.EpsIRIContent according to TS 33.108 Annex B.9, its value in the lawfulInterceptionIdentifier field of the encoded PDU shall be set to the fixed string "LIIDNotPresent".

When Option B specified in clause 6.3.1 is used:

• The IRI-POI present in the MME shall send the xIRIs over LI_X2 for each of the events listed in clause 12.2.1.1 of TS 33.107, the details of which are specified in clause 12.2.3 of the same TS, and in case of SMS over NAS as specified in clause 18.2.4 of TS 33.107.
• For all records except MMEIdentifierAssociation (see clause 6.3.2.2.2), the IRI-POI present in the MME shall set the payload format to EpsHI2Operations.EpsIRIContent (value 14), see clause 5.3 and ETSI TS 103 221-2 [8] clause 5.4. The payload field shall contain an EpsHI2Operations.EpsIRIContent structure encoded according to clauses 10.5, 15.2 and B.9 of TS 33.108.
• As the LIID may be not available at the MME but is mandatory in EpsHI2Operations.EpsIRIContent according to TS 33.108 Annex B.9, its value in the lawfulInterceptionIdentifier field of the encoded PDU shall be set to the fixed string "LIIDNotPresent".
• In addition to the xIRI events listed in TS 33.107, the MME shall support xIRI containing the MMEIdentiferAssociation record in clause 6.3.2.2.2.

The IRI-POI present in the MME shall generate an xIRI containing an MMEIdentifierAssociation record when the IRI-POI present in the MME detects a new identifier association for a UE matching one of the target identifiers provided via LI_X1. Generation of this record is subject to this record type being enabled for a specific target (see clause 6.3.2.2.1).

The IRI-POI present in the MME generating an xIRI containing an MMEIdentifierAssociation record shall set the Payload Direction field in the PDU header to not applicable (Direction Value 5, see ETSI TS 103 221-2 [8] clause 5.2.6). When transmitting the xIRI, the IRI-POI present in the MME shall set the payload format to 2, and provide the payload as a BER-encoded TS33128Payloads.XIRIPayloads structure.

The IRI-POI in the MME shall generate an xIRI containing an MMEAttach record when the IRI-POI present in the MME detects that a UE matching one of the target identifiers provided via LI_X1 has successfully attached to EPS. Accordingly, the IRI-POI in the MME generates the xIRI when the following event is detected:

• MME sends an S1: ATTACH ACCEPT message to the target UE and the UE EPS Mobility Management (EMM) state within the MME is changed to EMM-REGISTERED.

The IRI-POI in the MME shall generate an xIRI containing an MMEDetach record when the IRI-POI present in the MME detects that a UE matching one of the target identifiers provided via LI_X1 has deregistered from the EPS. Accordingly, the IRI-POI in the MME generates the xIRI when any of the following events is detected:

• For network initiated de-registration, when the MME receives the S1: DETACH ACCEPT message from the target UE, when the MME receives an S3: DETACH NOTIFICATION about the target UE from the SGSN or when implicit deregistration timer expires; and in all cases the UE EMM state within the MME is changed to EMM-DEREGISTERED.
• For UE initiated de-registration, when the MME sends the S1: DETACH ACCEPT message to the target UE or when the MME receives the S1: DETACH REQUEST message from the target UE with deregistration type value of "switch off"; and in both cases the UE EMM state within the MME is changed to EMM-DEREGISTERED.

The IRI-POI in the MME shall populate the ePSDetachType field with the values listed in Table 6.3.2-4 based on the Detach Type sent in the Detach Request message (see clause 9.9.3.7 of TS 24.301) and the direction of the Detach Request associated to the event that triggered the generation of the xIRI. If the Detach Request message associated to the event that triggered the generation of the xIRI has the EMM Cause field populated, the IRI-POI in the MME shall set the value of the cause field of the MMEDetach record to the integer value of the EMM Cause, see clause 9.9.3.9 of TS 24.301.

When the reporting of location information is authorised, the IRI-POI in the MME shall generate an xIRI containing an MMELocationUpdate record each time the IRI-POI present in an MME detects that the target UE location is updated due to target UE mobility or as a part of an MME service procedure. The generation of such separate xIRI is not required if the updated UE location information is obtained as a part of a procedure producing some other xIRIs (e.g. mobility registration). In that case the location information is included into the respective xIRI. In addition to the Tracking Area Update described in clause 5.3.3 of TS 23.401, the UE mobility events resulting in generation of an MMELocationUpdate xIRI include the S1 Path Switch Request (intra E-UTRAN handover X2 based handover procedure described in clause 5.5.1.1 of TS 23.401) and the S1 Handover Notify (Intra E-UTRAN S1 based handover procedure described in clause 5.5.1.2 of TS 23.401). The MMELocationUpdate xIRI is also generated when the MME receives an E-UTRAN S1AP ERAB Modification Indication message as a result of Dual Connectivity activation/release for the target UE, as described in clause 10 of TS 37.340. Based on regulatory requirements and operator policy, the location information obtained by the MME from E-UTRAN or the E-SMLC in the course of some service operations may result in the generation of the MMELocationUpdate xIRI record. Additionally, the IRI-POI in the MME shall capture the location information in the scenarios described in clause 4.4.2 of TS 23.271. Also, in the case of Mobile Originated LCS service invoked by the target, the location information may be derived from the Location Service Response sent to the target UE via the MME (see clause 9.2.6 of TS 23.271). Optionally, based on regulatory and operator policy, other MME messages that do not generate separate xIRI but carry location information such as emergency services or LCS may trigger the generation of an MMELocationUpdate xIRI record. The MMELocationUpdate record is also used by LARF to deliver location acquisition responses to MDF2, as described in clause 7.3.5.6. For the responses to location acquisition requests initiated by LARF, as described in TS 33.127 the MMELocationUpdate xIRIs shall not be generated.

The IRI-POI in the MME shall generate an xIRI containing an MMEStartOfInterceptionWithEPSAttachedUE record when the IRI-POI present in the MME detects that interception is activated on a UE that has already attached to the EPS. A UE is considered already attached to the EPS when the EMM state for that UE is EMM-REGISTERED. Therefore, the IRI-POI present in the MME shall generate the xIRI MMEStartOfInterceptionWithEPSAttachedUE record when it detects that a new interception for a UE is activated (i.e. provisioned by the LIPF) and the EPS mobility management state within the MME for that UE is EMM-REGISTERED.

The IRI-POI present in the MME generating an xIRI containing an MMEStartOfInterceptionWithEPSAttachedUE record shall set the Payload Direction field in the PDU header to not applicable (see ETSI TS 103 221-2 [8] clause 5.2.6).

The IRI-POI in the MME shall generate an xIRI containing an MMEUnsuccessfulProcedure record when the IRI-POI present in the MME detects an unsuccessful procedure for a UE matching one of the target identifiers provided via LI_X1. Accordingly, the IRI-POI in the MME generates the xIRI when any of the following events is detected:

• MME sends a reject to any EMM request message to the target UE and the UE EPS Mobility Management (EMM) within the MME is changed to EMM-DEREGISTERED.
• MME aborts a registration procedure before the UE EPS Mobility Management (EMM) state within the MME is changed to EMM-REGISTERED.
• MME sends a reject to any ESM request message to the target UE.

Unsuccessful attach attempts shall be reported only if the target UE has been successfully authenticated.

The IRI-POI present in the MME shall generate an xIRI containing an MMEPositioningInfoTransfer when the IRI-POI present in the MME detects one of the following events:

• a LPPa (see TS 36.455) message related to a target UE has been exchanged between the E-SMLC and the eNB via the MME.
• a LPP (see TS 37.355) message related to a target UE has been exchanged between the E-SMLC and the target UE via the MME.

Accordingly, the IRI-POI in MME generates the xIRI when any of the following events is detected:

• MME receives an SLs CONNECTION ORIENTED INFORMATION message (see TS 29.171) from E-SMLC to request the transfer of a LPPa request to the serving eNB for a target UE as part of a UE associated LPPa positioning activity. The LPPa request may be E-CID MEASUREMENT INITIATION REQUEST or OTDOA INFORMATION REQUEST.
• MME sends an SLs CONNECTION ORIENTED INFORMATION message to the E-SMLC to forward the LPPa response or report received from the eNB for a target UE. The LPPa response or report may be E-CID MEASUREMENT INITIATION RESPONSE, E-CID MEASUREMENT REPORT or OTDOA INFORMATION RESPONSE.
• MME receives an SLs CONNECTION ORIENTED INFORMATION message from E-SMLC to request the transfer of a LPP request to the target UE.
• MME sends an SLs CONNECTION ORIENTED INFORMATION message to E-SMLC to forward a LPP message received from the target UE.

The IRI-POI in the MME shall generate an xIRI containing an MMEUEServiceAccept record when the IRI-POI in present in the MME detects that the MME considers a service request procedure initiated by the target to be completed successfully (see clause 5.6.1.4 of TS 24.301).