This cause is sent to the MS if the MS is not known (registered) in the HLR. This cause indicates that the destination requested by the mobile station cannot be reached because, although the number is in a valid format, it is not currently assigned (allocated).Ĭause value = 2 IMSI unknown in HLR (Causes related to MS identification) 1 “unassigned (unallocated) number” (UMTS specific cause values for call control)
