Cause values for EPS mobility management

Cause values for EPS mobility management –

EPS Mobility Management (EMM) states are the states that result from the mobility management procedures e.g. Attach and Tracking Area Update procedures. UE can be detached from the network during these states and there could be different cause for that :-

a. Causes related to UE identification

Cause #2 – IMSI unknown in HSS - UEis not known (registered) in the HSS, orif the UE has packet only subscription

Cause #3 – Illegal UE - Network refuses service to the UE either because an identity of the UE is not acceptable, or

because the UE does not pass the authentication check

Cause #6 – Illegal ME - ME used is not acceptable to the network, e.g., blacklisted

Cause #9 – UE identity cannot be derived by network - Network cannot derive the UE's identity from the GUTI/S-TMSI/PTMSI and RAI

(e.g., failure to validate the UE's identity due to integrity check failure of the received message )

Cause #10 – Implicitly detached - Implicit detach timer has expired, or

EMM context data related to the subscription does not exist in the MME

b. Cause related to subscription options

Cause #5 – IMEI not accepted - Network does not accept an attach procedure for emergency bearer services using

Cause #7 – EPS services not allowed - UE is not allowed to operate EPS services

Cause #8 – EPS services & non-EPS services not allowed - UE is not allowed to operate EPS & non -EPS services

Cause #11 – PLMN not allowed - Network initiates a detach request, in a PLMN where the UE, by subscription or due to operator determined barring, is not allowed to operate

Cause #12 – Tracking area not allowed - Network initiates a detach request, in a tracking area where the HPLMN determines that the UE, by subscription, is not allowed to operate

c. Causes related to PLMN specific network failures and congestion/authentication failures

Cause #13 – Roaming not allow in tracking area - Network initiates a detach request, in a tracking area of a PLMN which by subscription offers roaming to that UE but not in that tracking area IMEI

Cause #14 – EPS services not allowed in this PLMN - Network initiates a detach request, in a PLMN which does not offer roaming for EPS services to that UE

Cause #15 – No suitable cells in tracking area - Network initiates a detach request, in a tracking area where the UE, by subscription, is not allowed to operate

Cause#40 – No EPS bearer context activated - During a tracking area updating procedure or a service request, the MME detects that there is no active EPS bearer context in the network

Cause #31 – Redirection to 5GCN required - UE by operator policy, is not allowed in EPC and redirection to 5GCN is required

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