In order to get a centralised handling of the security failures MTXV sends a Security Failure Notification Message (SFN) to HLR/MTXH at failed password check or Authentication.

This procedure is not used at failing password check at roaming updating or subscriber service procedure in MTXV as password check is carried out in HLR/MTXH in those cases.

HLR/MTXH returns Security Failure Notification Acknowledge (SFA) after notification of the security failure.

Figure 3.14: Security Failure Notification procedure