Section: 6.3.6.1 Authentication re-attempt
Content: The serving network sets the Authentication re-attempt to "true" if the second authentication described in the following cases results in an authentication failure report: - authentication with (P-)TMSI failed in MS (reject cause 'MAC failure') and new authentication procedure (re-attempt) is taken because an IMSI obtained by the followed IDENTITY REQUEST procedure does not match to the original IMSI that linked with (P-)TMSI. - authentication failed in MS (reject cause 'GSM authentication unacceptable') and new authentication procedure (re-attempt) is taken after MSC obtains UMTS authentication vectors from HLR. - authentication failed in MS (reject cause 'synch failure') and new authentication procedure (re-attempt) is taken after MSC obtains new authentication vectors from HLR for re-synchronisation. - SRES mismatches with (P-)TMSI in VLR/SGSN and new authentication procedure (re-attempt) is taken because an IMSI obtained by the followed IDENTITY REQUEST procedure does not match to the original IMSI that linked with (P-)TMSI. Otherwise Authentication re-attempt is set to "False".