3GPP 24.501 v20.0.0 — the document's own text
10.3 Timers of 5GS session management
Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).
Timers of 5GS session management are shown in table 10.3.1 and table 10.3.2.
NOTE: Timer T3396 is defined in 3GPP TS 24.008 [12].
Table 10.3.1: Timers of 5GS session management – UE side
| TIMER NUM. | TIMER VALUE | STATE | CAUSE OF START | NORMAL STOP | ON THE1st, 2nd, 3rd, 4th EXPIRY (NOTE 1) |
|---|---|---|---|---|---|
| T3580NOTE 4NOTE 5 | 16sIn WB-N1/CE mode, 24sFor access via a satellite NG-RAN cell, 21sNOTE 7 | PDU SESSION ACTIVE PENDING | Transmission of PDU SESSION ESTABLISHMENT REQUEST message | PDU SESSION ESTABLISHMENT ACCEPT message receivedorPDU SESSION ESTABLISHMENT REJECT message receivedorPDU SESSION ESTABLISHMENT REQUEST message received in a DL NAS TRANSPORT message with 5GMM cause #22, #28, #65, #67, #69, #90, #91 or #92 | Retransmission of PDU SESSION ESTABLISHMENT REQUEST message |
| T3581NOTE 4NOTE 5 | 16sIn WB-N1/CE mode, 24sFor access via a satellite NG-RAN cell, 21sNOTE 7 | PDU SESSION MODIFICATION PENDING | Transmission of PDU SESSION MODIFICATION REQUEST message | PDU SESSION MODIFICATION COMMAND message with the same PTI is receivedorPDU SESSION MODIFICATION REJECT message receivedorPDU SESSION MODIFICATION REQUEST message received in a DL NAS TRANSPORT message with 5GMM cause #22, #28, #67, #69, or #90 | Retransmission of PDU SESSION MODIFICATION REQUEST message |
| T3582NOTE 4NOTE 5 | 16sIn WB-N1/CE mode, 24sFor access via a satellite NG-RAN cell, 21sNOTE 7 | PDU SESSION INACTIVE PENDING | Transmission of PDU SESSION RELEASE REQUEST message | PDU SESSION RELEASE COMMAND message with the same PTI is received or PDU SESSION RELEASE REJECT message received | Retransmission of PDU SESSION RELEASE REQUEST message |
| T3583 | Default 1 min.NOTE 2 | PDU SESSION ACTIVE | UE creates or updates a derived QoS rule | UE deletes the derived QoS rule (see clause 6.2.5.1.4.5) | On 1st expiry: Deletion of the derived QoS rule |
| T3584 | NOTE 3 | PDU SESSION ACTIVE PENDINGPDU SESSION MODIFICATION PENDINGPDU SESSION ACTIVE or PDU SESSION INACTIVE PENDING | PDU SESSION ESTABLISHMENT REJECT, PDU SESSION MODIFICATION REJECT, or PDU SESSION RELEASE COMMAND received with 5GSM cause #67 and with a timer value for T3584PDU SESSION ESTABLISHMENT REQUEST, or PDU SESSION MODIFICATION REQUEST received in a DL NAS TRANSPORT message with 5GMM cause #67 and with a timer value for T3584 (see clause 5.4.5.3.3) | PDU SESSION RELEASE COMMAND message (see NOTE 6) or PDU SESSION MODIFICATION COMMAND message or PDU SESSION AUTHENTICATION COMMAND message or DEREGISTRATION REQUEST message with the De-registration type IE indicating "re-registration required" orREGISTRATION ACCEPT message orCONFIGURATION UPDATE COMMAND message (see clause 4.6.2.2)orDL NAS TRANSPORT message including a CIoT user data container without a 5GMM cause value (see clause 5.4.5.3.3) | None |
| T3585 | NOTE 3 | PDU SESSION ACTIVE PENDINGPDU SESSION MODIFICATION PENDINGPDU SESSION ACTIVE or PDU SESSION INACTIVE PENDING | PDU SESSION ESTABLISHMENT REJECT, PDU SESSION MODIFICATION REJECT, or PDU SESSION RELEASE COMMAND received with 5GSM cause #69 and with a timer value for T3585PDU SESSION ESTABLISHMENT REQUEST, or PDU SESSION MODIFICATION REQUEST received in a DL NAS TRANSPORT message with 5GMM cause #69 and with a timer value for T3585(see clause 5.4.5.3.3) | PDU SESSION RELEASE COMMAND message (see NOTE 6) or PDU SESSION MODIFICATION COMMAND message or PDU SESSION AUTHENTICATION COMMAND message or DEREGISTRATION REQUEST message with the De-registration type IE indicating "re-registration required" orREGISTRATION ACCEPT message orCONFIGURATION UPDATE COMMAND message (see clause 4.6.2.2)orDL NAS TRANSPORT message including a CIoT user data container without a 5GMM cause value (see clause 5.4.5.3.3) | None |
| Back-off timer | defined in 3GPP TS 24.008 [12] | ||||
| T3586NOTE 4NOTE 5 | 8sIn WB-N1/CE mode, 16sFor access via a satellite NG-RAN cell, 13sNOTE 7 | PDU SESSION ACTIVE | REMOTE UE REPORT message sent | REMOTE UE REPORT RESPONSE message received | On the 1st and 2nd expiry, retransmission of REMOTE UE REPORT messageOn the 3rd expiry, the procedure is aborted (see clause 6.6.2.4). |
| T3587 | NOTE 8 | PDU SESSION ACTIVE | PDU SESSION MODIFICATION COMMAND message or PDU SESSION ESTABLISHMENT ACCEPT message received with Received MBS information that includes MBS decision set to "MBS join is rejected" and Rejection cause set to "multicast MBS session has not started or will not start soon" and an MBS back-off timer value | None | Initiating a request to join the multicast MBS session associated with the PDU session if still needed |
| NOTE 1: Typically, the procedures are aborted on the fifth expiry of the relevant timer. Exceptions are described in the corresponding procedure description.NOTE 2: The network may provide the value of this timer applicable to the derived QoS rules of a specific PDU session as RQ timer value in the PDU SESSION ESTABLISHMENT ACCEPT message and PDU SESSION MODIFICATION COMMAND message. The maximum value of the timer is 30 min. If the network indicates a value greater than the maximum value, then the UE shall use the maximum value.NOTE 3: The value of this timer is provided by the network.NOTE 4: In NB-N1 mode, then the timer value shall be calculated as described in clause 4.18.NOTE 5: In WB-N1 mode, if the UE supports CE mode B and operates in either CE mode A or CE mode B, then the timer value is as described in this table for the case of WB-N1/CE mode (see clause 4.20).NOTE 6: If the PDU SESSION RELEASE COMMAND message includes the Back-off timer value IE where the timer value indicates neither zero nor deactivated and the 5GSM cause is not #39, the UE then starts the timer with the value provided in the Back-off timer value IE after stopping the existing timer (see clause 6.3.3.3).NOTE 7: In satellite NG-RAN access, this value shall only be selected when satellite NG-RAN RAT type is NR(MEO) or NR(GEO).NOTE 8: The value of this timer is provided by the network in the Received MBS container IE (see clause 6.3.2.3, clause 6.4.1.3 and clause 9.11.4.31). |
NOTE 1: The back-off timer is used to describe a logical model of the required UE behaviour. This model does not imply any specific implementation, e.g. as a timer of timestamp.
NOTE 2: Reference to back-off timer in this section can either refer to use of timer T3396 or to use of a different packet system specific timer within the UE. Whether the UE uses T3396 as a back-off timer or it uses different packet system specific timers as back-off timers is left up to UE implementation.
Table 10.3.2: Timers of 5GS session management – SMF side
| TIMER NUM. | TIMER VALUE | STATE | CAUSE OF START | NORMAL STOP | ON THE1st, 2nd, 3rd, 4th EXPIRY (NOTE 1) |
|---|---|---|---|---|---|
| T3590NOTE 3NOTE 4 | 15sIn WB-N1/CE mode, 23sFor access via a satellite NG-RAN cell, 21sNOTE 5 | PROCEDURE TRANSACTION PENDING | Transmission of PDU SESSION AUTHENTICATION COMMAND message | PDU SESSION AUTHENTICATION COMPLETE message received | Retransmission of PDU SESSION AUTHENTICATION COMMAND message |
| T3591NOTE 3NOTE 4 | 16sIn WB-N1/CE mode, 24sFor access via a satellite NG-RAN cell, 22sNOTE 5 | PDU SESSION MODIFICATION PENDING | Transmission of PDU SESSION MODIFICATION COMMAND message | PDU SESSION MODIFICATION COMPLETE message received or PDU SESSION MODIFICATION COMMAND REJECT message received | Retransmission of PDU SESSION MODIFICATION COMMAND message |
| T3592NOTE 3NOTE 4 | 16sIn WB-N1/CE mode, 24sFor access via a satellite NG-RAN cell, 22sNOTE 5 | PDU SESSION INACTIVE PENDING | Transmission of PDU SESSION RELEASE COMMAND message | PDU SESSION RELEASE COMPLETE message received orN1 SM delivery skipped indication received | Retransmission of PDU SESSION RELEASE COMMAND message |
| T3593NOTE 3NOTE 4 | Default60s(NOTE 2) | PDU SESSION MODIFICATION PENDING | Reception of PDU SESSION MODIFICATION COMPLETE message for transmitted PDU SESSION MODIFICATION COMMAND message where the PDU SESSION MODIFICATION COMMAND message included 5GSM cause #39 | PDU SESSION RELEASE REQUEST message received | Network-requested PDU session release procedure performed |
| T3594NOTE 3NOTE 4 | 15sIn WB-N1/CE mode, 23sFor access via a satellite NG-RAN cell, 21sNOTE 5 | PROCEDURE TRANSACTION PENDING | Transmission of SERVICE-LEVEL AUTHENTICATION COMMAND message | SERVICE-LEVEL AUTHENTICATION COMPLETE message received | Retransmission of SERVICE-LEVEL AUTHENTICATION COMMAND message |
| NOTE 1: Typically, the procedures are aborted on the fifth expiry of the relevant timer. Exceptions are described in the corresponding procedure description.NOTE 2: If the PDU Session Address Lifetime value is sent to the UE in the PDU SESSION MODIFICATION COMMAND message then timer T3593 shall be started with the same value, otherwise it shall use a default value.NOTE 3: In NB-N1 mode, the timer value shall be calculated as described in clause 4.18.NOTE 4: In WB-N1 mode, if the UE supports CE mode B and operates in either CE mode A or CE mode B, then the timer value is as described in this table for the case of WB-N1/CE mode (see clause 4.20).NOTE 5: In satellite NG-RAN access, this value shall only be selected when satellite NG-RAN RAT type is NR(MEO) or NR(GEO). |