Cause values for EPS mobility management
(A) Causes related to UE identification
Cause #2 – IMSI unknown in HSS
This EMM cause is sent to the UE if the UE is not known (registered) in the HSS or if the UE has packet only subscription. This EMM cause does not affect operation of the EPS service, although is may be used by an EMM procedure.
Cause #3 – Illegal UE
This EMM cause is sent to the UE when the network refuses service to the UE either because an identity of the UE is not acceptable to the network or because the UE does not pass the authentication check, i.e. the RES received from the UE is different from that generated by the network.
Cause #6 – Illegal ME
This EMM cause is sent to the UE if the ME used is not acceptable to the network, e.g. blacklisted.
Cause #9 – UE identity cannot be derived by the network.
This EMM cause is sent to the UE when the network cannot derive the UE’s identity from the GUTI/S-TMSI/P-TMSI and RAI e.g. no matching identity/context in the network or failure to validate the UE’s identity due to integrity check failure of the received message.
Cause #10 – Implicitly detached
This EMM cause is sent to the UE either if the network has implicitly detached the UE, e.g. after the implicit detach timer has expired, or if the EMM context data related to the subscription does not exist in the MME e.g. because of a MME restart, or because of a periodic tracking area update request routed to a new MME.
(B) Cause related to subscription options
Cause #5 – IMEI not accepted
This cause is sent to the UE if the network does not accept an attach procedure for emergency bearer services using an IMEI.
Cause #7 – EPS services not allowed
This EMM cause is sent to the UE when it is not allowed to operate EPS services.
Cause #8 – EPS services and non-EPS services not allowed
This EMM cause is sent to the UE when it is not allowed to operate either EPS or non-EPS services.
Cause #11 – PLMN not allowed
This EMM cause is sent to the UE if it requests service, or if the 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
This EMM cause is sent to the UE if it requests service, or if the network initiates a detach request, in a tracking area where the HPLMN determines that the UE, by subscription, is not allowed to operate.
NOTE 1: If EMM cause #12 is sent to a roaming subscriber the subscriber is denied service even if other PLMNs are available on which registration was possible.
Cause #13 – Roaming not allowed in this tracking area
This EMM cause is sent to an UE which requests service, or if the 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.
Cause #14 – EPS services not allowed in this PLMN
This EMM cause is sent to the UE which requests service, or if the network initiates a detach request, in a PLMN which does not offer roaming for EPS services to that UE.
NOTE 2: Since only one list of forbidden PLMNs for packet services is maintained in the UE, then the “forbidden PLMNs for GPRS service” is the maintained list and the forbidden PLMNs for EPS service is equivalent to it.
Cause #15 – No suitable cells in tracking area
This EMM cause is sent to the UE if it requests service, or if the network initiates a detach request, in a tracking area where the UE, by subscription, is not allowed to operate, but when it should find another allowed tracking area or location area in the same PLMN or an equivalent PLMN.
NOTE 3: Cause #15 and cause #12 differ in the fact that cause #12 does not trigger the UE to search for another allowed tracking area on the same PLMN.
Cause #25 – Not authorized for this CSG
This EMM cause is sent to the UE if it requests access, or if the network initiates a detach request, in a CSG cell with CSG ID where the UE either has no subscription to operate or the UE’s subscription has expired and it should find another cell in the same PLMN or an equivalent PLMN.
Cause #35 – Requested service option not authorized in this PLMN
This EMM cause is sent to the UE if it requests in a PLMN a service option for which it is not authorized, e.g. if it attempts to attach for relay node operation in a PLMN with a USIM which does not belong to a relay node-specific subscription.
Cause #40 – No EPS bearer context activated
This EMM cause is sent to the UE, if 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
This EMM cause is sent to the UE if it requests service in a PLMN where the UE by operator policy, is not allowed in EPC and redirection to 5GCN is required.
(C) Causes related to PLMN specific network failures and congestion/authentication failures
Cause #16 – MSC temporarily not reachable
This EMM cause is sent to the UE if it requests a combined EPS attach or tracking area updating in a PLMN where the MSC is temporarily not reachable via the EPS part of the network.
Cause #17 – Network failure
This EMM cause is sent to the UE if the MME cannot service an UE generated request because of PLMN failures.
Cause #18 – CS domain not available
This EMM cause is sent to the UE if the MME cannot service an UE generated request because CS domain is not available and SMS in MME is not supported.
Cause #19 – ESM failure
This EMM cause is sent to the UE when there is a failure in the ESM message contained in the EMM message.
Cause #20 – MAC failure
This EMM cause is sent to the network if the USIM detects that the MAC in the AUTHENTICATION REQUEST message is not fresh (see 3GPP TS 33.401 [19]).
Cause #21 – Synch failure
This EMM cause is sent to the network if the USIM detects that the SQN in the AUTHENTICATION REQUEST message is out of range (see 3GPP TS 33.401 [19]).
Cause #22 – Congestion
This EMM cause is sent to the UE because of congestion in the network (e.g. no channel, facility busy/congested etc.).
Cause #23 – UE security capabilities mismatch
This EMM cause is sent to the network if the UE detects that the UE security capability does not match the one sent back by the network.
Cause #24 – Security mode rejected, unspecified
This EMM cause is sent to the network if the security mode command is rejected by the UE if the UE detects that the nonceUE does not match the one sent back by the network or for unspecified reasons.
Cause #26 – Non-EPS authentication unacceptable
This EMM cause is sent to the network in S1 mode if the “separation bit” in the AMF field of AUTN is set to 0 in the AUTHENTICATION REQUEST message (see 3GPP TS 33.401 [19]).
Cause #39 – CS service temporarily not available
This EMM cause is sent to the UE when the CS fallback or 1xCS fallback request cannot be served temporarily due to O&M reasons or a mobile terminating CS fallback call is aborted by the network during call establishment (see 3GPP TS 29.118 [16A]).
Cause #42 – Severe network failure
This EMM cause is sent to the UE when the network has determined that the requested procedure cannot be completed successfully due to network failure. The failure is not expected to be temporary and repeated request is not likely to succeed in near future.
Cause values for EPS session management
(A) Causes related to nature of request
Cause #8 – Operator Determined Barring
This ESM cause is used by the network to indicate that the requested service was rejected by the MME due to Operator Determined Barring.
Cause #26 – Insufficient resources
This ESM cause is used by the UE or by the network to indicate that the requested service cannot be provided due to insufficient resources.
Cause #27 – Missing or unknown APN
This ESM cause is used by the network to indicate that the requested service was rejected by the external packet data network because the access point name was not included although required or if the access point name could not be resolved.
Cause #28 – Unknown PDN type
This ESM cause is used by the network to indicate that the requested service was rejected by the external packet data network because the PDN type could not be recognised.
Cause #29 – User authentication or authorization failed
This ESM cause is used by the network to indicate that the requested service was rejected by the external packet data network due to a failed user authentication or revoked by the external packet data network.
Cause #30 – Request rejected by Serving GW or PDN GW
This ESM cause is used by the network to indicate that the requested service or operation or the request for a resource was rejected by the Serving GW or PDN GW.
Cause #31 – Request rejected, unspecified
This ESM cause is used by the network or by the UE to indicate that the requested service or operation or the request for a resource was rejected due to unspecified reasons.
Cause #32 – Service option not supported
This ESM cause is used by the network when the UE requests a service which is not supported by the PLMN.
Cause #33 – Requested service option not subscribed
This ESM cause is sent when the UE requests a service option for which it has no subscription.
Cause #34 – Service option temporarily out of order
This ESM cause is sent when the network cannot service the request because of temporary outage of one or more functions required for supporting the service.
Cause #35 – PTI already in use
This ESM cause is used by the network to indicate that the PTI included by the UE is already in use by another active UE requested procedure for this UE.
Cause #36 – Regular deactivation
This ESM cause is used to indicate a regular UE or network initiated release of EPS bearer resources.
Cause #37 – EPS QoS not accepted
This ESM cause is used by the network if the new EPS QoS cannot be accepted that was indicated in the UE request.
Cause #38 – Network failure
This ESM cause is used by the network to indicate that the requested service was rejected due to an error situation in the network.
Cause #39 – Reactivation requested
This ESM cause is used by the network to request a PDN connection reactivation.
Cause #41 – Semantic error in the TFT operation.
This ESM cause is used by the network or the UE to indicate that the requested service was rejected due to a semantic error in the TFT operation included in the request.
Cause #42 – Syntactical error in the TFT operation.
This ESM cause is used by the network or the UE to indicate that the requested service was rejected due to a syntactical error in the TFT operation included in the request.
Cause #43 – Invalid EPS bearer identity
This ESM cause is used by the network or the UE to indicate that the EPS bearer identity value provided to it is not a valid value for the received message or the EPS bearer context identified by the linked EPS bearer identity IE in the request is not active.
Cause #44 – Semantic errors in packet filter(s)
This ESM cause is used by the network or the UE to indicate that the requested service was rejected due to one or more semantic errors in packet filter(s) of the TFT included in the request.
Cause #45 – Syntactical error in packet filter(s)
This ESM cause is used by the network or the UE to indicate that the requested service was rejected due to one or more syntactical errors in packet filter(s) of the TFT included in the request.
Cause #47 – PTI mismatch
This ESM cause is used by the UE to indicate that the PTI value which is included in the ESM message that the UE receives does not match a PTI in use.
Cause #49 – Last PDN disconnection not allowed
This ESM cause is used by the network, in case of EMM-REGISTERED without PDN connection is not supported by the UE or the MME, to indicate that the UE requested PDN disconnection procedure on the last remaining PDN connection is not allowed.
Cause #50 – PDN type IPv4 only allowed
This ESM cause is used by the network to indicate that only PDN type IPv4 is allowed for the requested PDN connectivity.
Cause #51 – PDN type IPv6 only allowed
This ESM cause is used by the network to indicate that only PDN type IPv6 is allowed for the requested PDN connectivity.
Cause #52 – single address bearers only allowed
This ESM cause is used by the network to indicate that the requested PDN connectivity is accepted with the restriction that only single IP version bearers are allowed.
Cause #53 – ESM information not received
This ESM cause is used by the network to indicate that the PDN connectivity procedure was rejected due to the ESM information was not received.
Cause #54 – PDN connection does not exist
This ESM cause is used by the network at handover from a non-3GPP access network to indicate that the MME does not have any information about the requested PDN connection.
Cause #55 – Multiple PDN connections for a given APN not allowed
This ESM cause is used by the network to indicate that the PDN connectivity procedure was rejected due to multiple PDN connections for a given APN are not allowed.
Cause #56 – Collision with network initiated request
This ESM cause is used by the network to indicate that the network has already initiated the activation, modification or deactivation of bearer resources which was requested by the UE.
Cause #57 – PDN type IPv4v6 only allowed
This ESM cause is used by the network to indicate that only PDN types IPv4, IPv6 or IPv4v6 are allowed for the requested PDN connectivity.
Cause #58 – PDN type non IP only allowed
This ESM cause is used by the network to indicate that only PDN type non IP is allowed for the requested PDN connectivity.
Cause #59 – Unsupported QCI value
This ESM cause is used by the network if the QCI indicated in the UE request cannot be supported.
Cause #60 – Bearer handling not supported
This ESM cause is used by the network to indicate that the procedure requested by the UE was rejected because the bearer handling is not supported.
Cause #61 – PDN type Ethernet only allowed
This ESM cause is used by the network to indicate that only PDN type Ethernet is allowed for the requested PDN connectivity.
Cause #65 – Maximum number of EPS bearers reached
This ESM cause is used by the network to indicate that the procedure requested by the UE was rejected as the network has reached the maximum number of simultaneously active EPS bearer contexts for the UE.
Cause #66 – Requested APN not supported in current RAT and PLMN combination
This ESM cause is used by the network to indicate that the procedure requested by the UE was rejected as the requested APN is not supported in the current RAT and PLMN.
Cause #81 – Invalid PTI value
This ESM cause is used by the network or UE to indicate that the PTI provided to it is unassigned or reserved.
Cause #112 – APN restriction value incompatible with active EPS bearer context.
This ESM cause is used by the network to indicate that the EPS bearer context(s) have an APN restriction value that is not allowed in combination with a currently active EPS bearer context. Restriction values are defined in 3GPP TS 23.060 [4].
Cause #113 –Multiple accesses to a PDN connection not allowed
This ESM cause is used by the network to indicate that multiple accesses to a PDN connection for NBIFOM is not allowed.
(B) Protocol errors (e.g., unknown message) class
Cause #95 – Semantically incorrect message
This ESM cause is used to report receipt of a message with semantically incorrect contents.
Cause #96 – Invalid mandatory information
This ESM cause indicates that the equipment sending this ESM cause has received a message with a non-semantical mandatory IE error.
Cause #97 – Message type non-existent or not implemented
This ESM cause indicates that the equipment sending this ESM cause has received a message with a message type it does not recognize either because this is a message not defined, or defined but not implemented by the equipment sending this ESM cause.
Cause #98 – Message type not compatible with protocol state
This ESM cause indicates that the equipment sending this ESM cause has received a message not compatible with the protocol state.
Cause #99 – Information element non-existent or not implemented
This ESM cause indicates that the equipment sending this ESM cause has received a message which includes information elements not recognized because the information element identifier is not defined or it is defined but not implemented by the equipment sending the ESM cause. However, the information element is not required to be present in the message in order for the equipment sending the ESM cause to process the message.
Cause #100 – Conditional IE error
This ESM cause indicates that the equipment sending this cause has received a message with conditional IE errors.
Cause #101 – Message not compatible with protocol state
This ESM cause indicates that a message has been received which is incompatible with the protocol state.
Cause #111 – Protocol error, unspecified
This ESM cause is used to report a protocol error event only when no other ESM cause in the protocol error class applies.
Source: 3GPP 24.301, for latest update please visit 3GPP official file location