Section: 10.5.4.11 Cause
Content: The purpose of the cause information element is to describe the reason for generating certain messages, to provide diagnostic information in the event of procedural errors and to indicate the location of the cause originator. The cause information element is coded as shown in figure 10.5.95/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  and tables 10.5.122 and 10.5.123/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ] . The cause is a type 4 information element with a minimum length of 4 octets and a maximum length of 32 octets. The cause information element may be repeated in a message. Figure 10.5.95/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  Cause information element If the default value applies for the recommendation field, octet 3a shall be omitted. Table 10.5.122/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ] : Cause information element Table 10.5.122/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ] : Cause information element (continued) Table 10.5.123/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ] : Cause information element values Table 10.5.123/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  (concluded): Cause information element values All other values in the range 0 to 31 shall be treated as cause 31. All other values in the range 32 to 47 shall be treated as cause 47. All other values in the range 48 to 63 shall be treated as cause 63. All other values in the range 64 to 79 shall be treated as cause 79. All other values in the range 80 to 95 shall be treated as cause 95. All other values in the range 96 to 111 shall be treated as cause 111. All other values in the range 112 to 127 shall be treated as cause 127. NOTE 1: Diagnostics for supplementary services are handled as follows: octet 5, bit 8: This is an extension bit as defined in the preliminary part of subclause 10.5. In this version of this protocol, this bit shall be set to 1. If it is set to zero, the contents of the following octets shall be ignored. octet 5, bit 7-1: 0000001 - Outgoing calls barred within CUG 0000010 - No CUG selected 0000011 - Unknown CUG index 0000100 - CUG index incompatible with requested basic service 0000101 - CUG call failure, unspecified 0000110 - CLIR not subscribed 0000111 - CCBS possible 0001000 - CCBS not possible All other values shall be ignored. NOTE 2: The incompatible parameter is composed of the incompatible information element identifier. NOTE 3: The format of the diagnostic field for cause numbers 57, 58 and 65 is as shown in figure 10.5.88/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  and tables 10.5.102/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  to 10.5.115/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ] . NOTE 4: The user supplied diagnostics field is encoded according to the user specification, subject to the maximum length of the cause information element. The coding of user supplied diagnostics should be made in such a way that it does not conflict with the coding described in note 9 below. NOTE 5: The new destination is formatted as the called party BCD number information element, including information element identifier. NOTE 6: Locking and non-locking shift procedures described in subclause 10.5.4.2 and clause 3 are applied. In principle, information element identifiers are ordered in the same order as the information elements in the received message. NOTE 7: When only the locking shift information element is included and no information element identifier follows, it means that the codeset in the locking shift itself is not implemented. NOTE 8: The timer number is coded in IA5 characters, e.g., T308 is coded as "3" "0" "8". The following coding is used in each octet: bit 8: spare "0" bits 7-1: IA5 character Octet 5 carries "3", octet 5a carries "0", etc. NOTE 9: The following coding is used for octet 5: bit 8 : 1 bits 7-3: 00000 bits 2-1: condition as follows: 00 - unknown 01 - permanent 10 - transient