5G NAS DL TRANSPORT Raw decoding issue

Dear support,

I'm facing an issue using the RAW codec in TITAN. The NAS pdu value is: '7E03AF406FE0007E005D020402F0F0E1360102'O This is a NG_SECURITY_PROTECTED_NAS_MESSAGE containing a NG SECURE MODE COMMAND.

In the demo project, the file ttcn/Lib3GPP/NG_NAS/NG_NAS_MsgContainers.ttcn provides the NG_NAS_DL_Message_Type with following variant:

type union NG_NAS_DL_Message_Type {  /* NAS message with direction 'network to UE' or 'both' */
    NG_SECURITY_PROTECTED_NAS_MESSAGE                      security_Protected_Nas_Message,
    NG_AUTHENTICATION_REJECT                               authentication_Reject,
    ...
 } with { 
    variant "TAG(
      security_Protected_Nas_Message, securityHeaderType = '0001'B;
      security_Protected_Nas_Message, securityHeaderType = '0010'B;
      security_Protected_Nas_Message, securityHeaderType = '0011'B;
      security_Protected_Nas_Message, securityHeaderType = '0100'B;
      registration_Accept,            messageType = '01000010'B;
      authentication_Request,         messageType = '01010110'B;
      security_Mode_Command,          messageType = '01011101'B;
      configuration_Update_Command,   messageType = '01010100'B;
      dl_Nas_Transport,               messageType = '01101000'B;
    )"
}

It is very close to what was done here.

The issue is that based on these variant, the NAS PDU is decoded as NG_AUTHENTICATION_RESULT.

Please, can you indicate me what's was wrong in my process?

Many thanks in advance,

Yann Garcia FSCOM ETSI TTF 041