Section: 8.49 Fully Qualified Cause (F-Cause)
Content: Fully Qualified Cause (F- Cause) is coded as depicted in Figure 8.49-1. Figure 8.49-1: Full Qualified Cause (F-Cause) The value of Instance field of the F-Cause IE in a GTPv2 message shall indicate whether the F-Cause field contains RANAP Cause, BSSGP Cause or S1-AP Cause. All spare bits shall be set to zeros by the sender and ignored by the receiver. F-Cause field is coded as follows: - For RANAP Cause, the F-Cause field shall contain a non-transparent copy of the cause value of the corresponding IE (see clause 8.2.2), "Cause", as defined in clause 9.2..4 in 3GPP TS 25.413[ UTRAN Iu interface Radio Access Network Application Part (RANAP) signalling ]  [33]. Cause Type field shall be ignored by the receiver. The value of F-Cause field (which has a range of 1..512) is transferred over the Iu interface and encoded into two octet as binary integer. - For BSSGP Cause, the F-Cause field shall contain a non-transparent copy of the cause value of the corresponding IE (see clause 8.2.2), "Cause", as defined in clause 11.3.8 in 3GPP TS 48.018[ None ]  [34]. Cause Type field shall be ignored by the receiver. The value of F-Cause field (which has a range of 0..255) is transferred over the Gb interface and encoded into one octet as binary integer. - For S1-AP Cause, the F-Cause field shall contain a non-transparent copy of the cause value of the corresponding IE (see clause 8.2.2), "Cause", as defined in clause 9.2.1.3 in 3GPP TS 36.413[ Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 Application Protocol (S1AP) ]  [10]. Cause Type field shall contain the RAN Cause subcategory as specified in 3GPP TS 36.413[ Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 Application Protocol (S1AP) ]  [10] and it shall be encoded as in Table 8.49-1. The value of F-Cause field (and the associated RAN cause subcategory) is transferred over the S1-AP interface and encoded into one octet as binary integer. Table 8.49-1: Cause Type values and their meanings