Section: 14.3 Root NAI
Content: The Root NAI shall take the form of a NAI, and shall have the form username@realm as specified in clause 2.1 of IETF RFC 4282 [53]. The username part format of the Root NAI shall comply with IETF RFC 4187 [50] when EAP AKA authentication is used and with IETF RFC 4186 [51], when EAP SIM authentication is used. When the username part includes the IMSI, the Root NAI shall be built according to the following steps: 1. Generate an identity conforming to NAI format from IMSI as defined in EAP SIM [51] and EAP AKA [50] as appropriate; 2. Convert the leading digits of the IMSI, i.e. MNC and MCC, into a domain name, as described in clause 14.2. The result will be a root NAI of the form: "0<IMSI>@wlan.mnc<MNC>.mcc<MCC>.3gppnetwork.org", for EAP AKA authentication and "1<IMSI>@wlan.mnc<MNC>.mcc<MCC>.3gppnetwork.org", for EAP SIM authentication For example, for EAP AKA authentication: If the IMSI is 234150999999999 (MCC = 234, MNC = 15), the root NAI then takes the form 0234150999999999@wlan.mnc015.mcc234.3gppnetwork.org.