Section: B.1 Representation of IMEI
Content: The International Mobile station Equipment Identity and Software Version number (IMEISV), as defined in clause 6, is a 16 digit decimal number composed of three distinct elements: - an 8 digit Type Allocation Code (TAC); - a 6 digit Serial Number (SNR); and - a 2 digit Software Version Number (SVN). The IMEISV is formed by concatenating these three elements as illustrated below: Figure A.1: Composition of the IMEISV The IMEI is complemented by a check digit as defined in clause 3. The Luhn Check Digit (CD) is computed on the 14 most significant digits of the IMEISV, that is on the value obtained by ignoring the SVN digits. The method for computing the Luhn check is defined in Annex B of the International Standard "Identification cards - Numbering system and registration procedure for issuer identifiers" (ISO/IEC 7812 [3]). In order to specify precisely how the CD is computed for the IMEI, it is necessary to label the individual digits of the IMEISV, excluding the SVN. This is done as follows: The (14 most significant) digits of the IMEISV are labelled D14, D13 ... D1, where: - TAC = D14, D13 ... D7 (with D7 the least significant digit of TAC); - SNR = D6, D5 ... D1 (with D1 the least significant digit of SNR).