Mobile Communication

GSM Attach Procedure GSM initial attach to the network, step by step messages from Network <=> MS 1. [0x5B2F/002/129] | OTA LOG | 07:21:52.178 | GSM DSDS RR Signaling Message Channel Type = RACH (2) Direction = Uplink Message Type = Open Loop CMD ACK (129) Message Length in bytes = 24 L3 Message in Hex:   17 49 06 1B 3E 46 04 F4 94 00 2A C8 00 0A 14 65 4A B8 00 00 81 00 05 9B Decoded Message: prot_disc = 7 (0x7) (GSM_EPS_MOB_MANAGEMENT) msg_type = 73 (0x49) 2.0 0x5B2F/002/129] | OTA LOG | 07:21:52.178 | GSM DSDS RR Signaling Message Channel Type = BCCH (1) Direction = Uplink Message Type = System Information Type 9 (4) Message Length in bytes = 19 L3 Message in Hex:   12 06 15 AB EB 7E 00 00 00 00 00 00 00 00 00 00 00 00 00 Decoded Message: prot_disc = 6 (0x6) (GSM_RR_MANAGEMENT) msg_type = 21 (0x15) MEASUREMENT_REPORT BA_USED = 1 (0x1) DTX_USED = 0 (0x0) RXLEV_FULL_SERVING_CELL = 43 (0x2b) 3G_BA_USED = 1 (0x1) ME...

C AUSE CODES   FROM   NETWORK   Reference : 3GPP TS 24.008 10.5.3.6 and Annex G. Cause  No  1  :    “unassigned (unallocated) number” (UMTS specific cause values for call control) 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). Cause value = 2  : IMSI unknown in HLR (Causes related to MS identification) This cause is sent to the MS if the MS is not known (registered) in the HLR. This cause code  does not affect operation of the GPRS service, although is may be used by a GMM procedure. Cause value = 3  :   Illegal MS (Causes related to MS identification)   This cause is sent to the MS when the network refuses service to the MS either because an  identity of the MS is not acceptable to the network or because the MS does not pass the authenticat...