Section: 15.2 Structure of TMGI
Content: Temporary Mobile Group Identity (TMGI) is used within MBMS to uniquely identify Multicast and Broadcast bearer services. TMGI is composed as shown in figure 15.2.1. Figure 15.2.1: Structure of TMGI The TMGI is composed of three parts: 1) MBMS Service ID consisting of three octets. MBMS Service ID consists of a 6-digit fixed-length hexadecimal number between 000000 and FFFFFF. MBMS Service ID uniquely identifies an MBMS bearer service within a PLMN. The structure of MBMS Service ID for services for Receive only mode is defined in 3GPP TS 24.116[ Stage 3 aspects of system architecture enhancements for TV services ]  [118]. 2) Mobile Country Code (MCC) consisting of three digits. The MCC identifies uniquely the country of domicile of the BM-SC, except for the MCC value of 901, which does not identify any country and is assigned globally by ITU; 3) Mobile Network Code (MNC) consisting of two or three digits (depending on the assignment to the PLMN by its national numbering plan administrator). The MNC identifies the PLMN which the BM-SC belongs to, except for the MNC value of 56 when the MCC value is 901, which does not identify any PLMN. For more information on the use of the TMGI, see 3GPP TS 23.246[ Multimedia Broadcast/Multicast Service (MBMS); Architecture and functional description ]  [52]. Any TMGI with MCC=901 and MNC=56 is used only for services for Receive Only Mode (see TS 23.246[ Multimedia Broadcast/Multicast Service (MBMS); Architecture and functional description ]  [52] and 3GPP TS 24.116[ Stage 3 aspects of system architecture enhancements for TV services ]  [118]).