In TS24.501 Ch 5.5.1.3.8 Abnormal cases on the network side
d) REGISTRATION REQUEST with 5GS registration type IE set to
"mobility registration updating" or "periodic registration updating"
received after the REGISTRATION ACCEPT message has been sent and
before the REGISTRATION COMPLETE message is received.
Since, we have to do this special case, it is desirable
to handle it directly inside the state(gmm-sm.c).
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RX : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
GX : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
PFCP : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
RULE : Source <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> Destination <UE_IP> <UE_PORT>
TFT : Local <UE_IP> <UE_PORT> REMOTE <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
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RX : permit in from <UE_IP> <UE_PORT> to <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
GX : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
PFCP : permit out from <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT> to <UE_IP> <UE_PORT>
RULE : Source <UE_IP> <UE_PORT> Destination <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
TFT : Local <UE_IP> <UE_PORT> REMOTE <P-CSCF_RTP_IP> <P-CSCF_RTP_PORT>
o Tester
1. UE registered to 5GS and can connect to internet.
2. Turn off the UE and turn on the UE immediately
3. UE send PDU session request message
without sending registration complete
o Analysis Result
1. UE sends registration request with unknown GUTI
2. AMF send registration accept without GUTI
3. UE skips the registration complete
So, we need the handler UL NAS Transport in this state.
