6 MME – EIR (S13) and SGSN – EIR (S13′)
29.2723GPPEvolved Packet System (EPS)Mobility Management Entity (MME) and Serving GPRS Support Node (SGSN) related interfaces based on Diameter protocolRelease 17TS
6.1 Introduction
The S13 interface shall enable the ME Identity check procedure between the MME and the EIR as described in the 3GPP TS 23.401 [2].
The S13′ interface shall enable the ME Identity check procedure between the SGSN and the EIR as described in the 3GPP TS 23.060 [12].
6.2 ME Identity Check Procedures
6.2.1 ME Identity Check
6.2.1.1 General
This Mobile Equipment Identity Check Procedure shall be used between the MME and the EIR and between the SGSN and the EIR to check the Mobile Equipment’s identity status (e.g. to check that it has not been stolen, or, to verify that it does not have faults).
This procedure is mapped to the commands ME-Identity-Check-Request/Answer (ECR/ECA) in the Diameter application specified in clause 6.
Table 6.2.1.1/1 specifies the involved information elements for the request.
Table 6.2.1.1/2 specifies the involved information elements for the answer.
Table 6.2.1.1/1: ME Identity Check Request
|
Information element name |
Mapping to Diameter AVP |
Cat. |
Description |
|
Terminal Information (See 7.3.3) |
Terminal-Information |
M |
This information element shall contain the information about the used mobile equipment i.e. the IMEI. Within this Information Element, only the IMEI and the Software-Version AVPs shall be used on the S13/S13′ interface. |
|
IMSI |
User-Name (See IETF RFC 6733 [61]) |
O |
This information element shall contain the user IMSI, formatted according to 3GPP TS 23.003 [3], clause 2.2. |
Table 6.2.1.1/2: ME Identity Check Answer
|
Information element name |
Mapping to Diameter AVP |
Cat. |
Description |
|
Result (See 7.4) |
Result-Code / Experimental-Result |
M |
This IE shall contain the result of the operation. The Result-Code AVP shall be used to indicate success / errors as defined in the Diameter base protocol (see IETF RFC 6733 [61]). The Experimental-Result AVP shall be used for S13/S13′ errors. This is a grouped AVP which shall contain the 3GPP Vendor ID in the Vendor-Id AVP, and the error code in the Experimental-Result-Code AVP. The following errors are applicable in this case: – Unknown equipment |
|
Equipment Status (See 7.3.51) |
Equipment-Status |
C |
This information element shall contain the status of the requested mobile equipment as defined in 3GPP TS 22.016 [13]. It shall be present if the result of the ME Identity Check is DIAMETER_SUCCESS. |
6.2.1.2 Detailed behaviour of the MME and the SGSN
The MME or the SGSN shall make use of this procedure to check the ME identity, if the MME or the SGSN is configured to check the IMEI with the EIR.
Terminal-Information, when sent by the MME/SGSN to the EIR, shall contain the IMEI AVP, and it may contain also the Software-Version AVP.
IMSI may be sent together with Terminal Information to the EIR for operator-determined purposes.
When receiving the ME Identity Check answer from the EIR, the MME or the SGSN shall check the result code and the equipment status. Dependent upon the result, the MME or the SGSN will decide its subsequent actions (e.g. sending an Attach Reject if the EIR indicates that the Mobile Equipment is unknown or prohibited listed).
6.2.1.3 Detailed behaviour of the EIR
When receiving an ME Identity Check request, the EIR shall check whether the mobile equipment is known.
The EIR shall identify the mobile equipment based on the first 14 digits of the IMEI AVP; if a 15th digit is received in the IMEI AVP, this digit shall be ignored by the EIR.
Based on operator policies, the EIR may also use the Software-Version AVP, in addition to the first 14 digits of the IMEI AVP, to check the equipment identity against prohibited and tracking lists (see 3GPP TS 22.016 [13]).
If the mobile equipment identity is not known, a result code of DIAMETER_ERROR_ EQUIPMENT_UNKNOWN is returned.
If it is known, the EIR shall return DIAMETER_SUCCESS with the equipment status.