6 Elementary procedures between TSN AF and NW-TT

24.5193GPP5G System (5GS)Release 16Stage 3Time-Sensitive Networking (TSN) Application Function (AF) to Device-Side TSN Translator (DS-TT) and Network-Side TSN Translator (NW-TT) protocol aspectsTS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

6.1 General

The TSN AF and NW-TT supports transfer of standardized and deployment-specific Ethernet port management information, to manage the Ethernet port used at the NW-TT. The TSN AF and NW-TT supports transfer of standardized and deployment-specific Bridge management information, to manage the NW-TT. The Ethernet port management messages are included in the "PortManagementContainer" data type (as specified in 3GPP TS 29.512 [5B]) and the Port Management Information Container IE (as specified in 3GPP TS 29.244 [5A]) and the Bridge management messages are included in the "BridgeManagementContainer" data type (as specified in 3GPP TS 29.512 [5B]) and the Bridge Management Information Container IE (as specified in 3GPP TS 29.244 [5A]). Both the Ethernet port management messages and the Bridge management messages are transported using the N4 Session Level Reporting Procedure and the SM policy association modification procedure as specified in 3GPP TS 23.502 [3].

6.2 Procedures for Ethernet port management service

6.2.1 TSN AF-requested Ethernet port management procedure

6.2.1.1 General

The purpose of the TSN AF-requested Ethernet port management procedure is to enable the TSN AF to:

a) obtain the list of port management parameters supported by the NW-TT;

b) obtain the current values of port management parameters at the NW-TT Ethernet port;

c) set the values of port management parameters at the NW-TT Ethernet port; or

d) subscribe to be notified by the NW-TT if the values of certain port management parameters change at the NW-TT Ethernet port;

e) unsubscribe to be notified by the NW-TT for one or more port management parameters; or

f) delete a port management parameter-entry at the NW-TT Ethernet port.

6.2.1.2 TSN AF-requested Ethernet port management procedure initiation

In order to initiate the TSN AF-requested Ethernet port management procedure, the TSN AF shall:

a) encode the information about the port management parameters values to be read, the port management parameters values to be set, the port management parameters changes to (un)subscribe to, the port management parameter-entry to be deleted and whether the TSN AF requests the list of port management parameters supported by the NW-TT in an Ethernet port management list IE as specified in clause 9.2 and include it in a MANAGE ETHERNET PORT COMMAND message;

b) send the MANAGE ETHERNET PORT COMMAND message to the NW-TT via the PCF and the SMF as specified in 3GPP TS 23.502 [3]; and

c) start timer T100 (see example in figure 6.2.1.2.1).

Figure 6.2.1.2.1: TSN AF-requested Ethernet port management procedure

6.2.1.3 TSN AF-requested Ethernet port management procedure completion

Upon receipt of the MANAGE ETHERNET PORT COMMAND message, for each operation included in the Ethernet port management list IE, the NW-TT shall:

a) if the operation code is "get capabilities", include the list of Ethernet port management parameters supported by the NW-TT in the Ethernet port management capability IE of the MANAGE ETHERNET PORT COMPLETE message;

b) if the operation code is "read parameter", attempt to read the value of the parameter at the NW-TT Ethernet port, and:

1) if the value of the parameter at the NW-TT Ethernet port is read successfully, include the parameter and its current value in the Ethernet port status IE of the MANAGE ETHERNET PORT COMPLETE message; and

2) if the value of the parameter at the NW-TT Ethernet port was not read successfully, include the parameter and associated Ethernet port management service cause value in the Ethernet port status IE of the MANAGE ETHERNET PORT COMPLETE message;

c) if the operation code is "set parameter", attempt to set the value of the parameter at the NW-TT Ethernet port to the value specified in the operation, and:

1) if the value of the parameter at the NW-TT Ethernet port is set successfully, include the parameter and its current value in the Ethernet port update result IE of the MANAGE ETHERNET PORT COMPLETE message; and

2) if the value of the parameter at the NW-TT Ethernet port was not set successfully, include the parameter and associated Ethernet port management service cause value in the Ethernet port update result IE of the MANAGE ETHERNET PORT COMPLETE message;

d) if the operation code is "subscribe-notify for parameter", store the request from the TSN AF to be notified of changes in the value of the corresponding parameter;

e) if the operation code is "unsubscribe for parameter", delete the stored request from the TSN AF to be notified of changes in the value of the corresponding parameter, if any;

i) if the operation code is "delete parameter-entry", attempt to delete the referred parameter-entry of the parameter at the NW-TT Ethernet port; and

1) if the parameter-entry of the parameter at the NW-TT Ethernet port is deleted successfully, include the parameter and its current value in the Ethernet port update result IE of the MANAGE ETHERNET PORT COMPLETE message; and

2) if the parameter-entry of the parameter at the NW-TT Ethernet port was not deleted successfully, include the parameter and associated Ethernet port management service cause value in the Ethernet port update result IE of the MANAGE ETHERNET PORT COMPLETE message; and

f) send the MANAGE ETHERNET PORT COMPLETE to the TSN AF via the SMF and the PCF as specified in 3GPP TS 23.502 [3].

6.2.1.4 Abnormal cases in the TSN AF

The following abnormal cases can be identified:

a) T100 expired.

The TSN AF shall, on the first expiry of the timer T100, retransmit the MANAGE ETHERNET PORT COMMAND message and shall reset and start timer T100. This retransmission is repeated four times, i.e. on the fifth expiry of timer T35xx, the TSN AF shall abort the procedure.

6.2.1.5 Abnormal cases in the NW-TT

The following abnormal cases can be identified:

a) Transmission failure of the MANAGE ETHERNET PORT COMPLETE message indication from lower layers.

The NW-TT shall not diagnose an error and consider the TSN AF-initiated Ethernet port management procedure complete.

NOTE: Considering that the TSN AF-initiated Ethernet port management procedure complete as a result of this abnormal case does not cause the NW-TT to revert the execution of the operations included in the MANAGE ETHERNET PORT COMMAND message.

6.2.2 NW-TT-initiated Ethernet port management procedure

6.2.2.1 General

The purpose of the NW-TT-initiated Ethernet port management procedure is to notify the TSN AF of one or more changes in the value of Ethernet port management parameters for which the TSN AF had requested to be notified of changes via the TSN AF-initiated Ethernet port management procedure.

6.2.2.2 NW-TT-initiated Ethernet port management procedure initiation

In order to initiate the NW-TT-initiated Ethernet port management procedure, the NW-TT shall create an ETHERNET PORT MANAGEMENT NOTIFY message and shall:

a) include the Ethernet port management parameters to be reported to the TSN AF with their current value in the Ethernet port status IE of the ETHERNET PORT MANAGEMENT NOTIFY message;

b) start timer T300; and

c) send the ETHERNET PORT MANAGEMENT NOTIFY message to the TSN AF via the SMF and the PCF as specified in 3GPP TS 23.502 [3].

Figure 6.2.2.2.1: NW-TT-initiated Ethernet port management procedure

6.2.2.3 NW-TT-initiated Ethernet port management procedure completion

Upon receipt of the ETHERNET PORT MANAGEMENT NOTIFY message, the TSN AF shall:

a) create an ETHERNET PORT MANAGEMENT NOTIFY ACK message; and

b) send the ETHERNET PORT MANAGEMENT NOTIFY ACK message to the NW-TT via the PCF and the SMF as specified in 3GPP TS 23.502 [3].

Upon receipt of the ETHERNET PORT MANAGEMENT NOTIFY ACK message, the NW-TT shall stop timer T300.

6.2.2.4 Abnormal cases in the TSN AF

The following abnormal cases can be identified:

a) Transmission failure of the ETHERNET PORT MANAGEMENT NOTIFY ACK indication from lower layers.

The TSN AF shall not diagnose an error and consider the NW-TT-initiated Ethernet port management procedure complete.

6.2.2.5 Abnormal cases in the NW-TT

The following abnormal cases can be identified:

a) T300 expired.

The NW-TT shall, on the first expiry of the timer T300, retransmit the ETHERNET PORT MANAGEMENT NOTIFY message and shall reset and start timer T300. This retransmission is repeated four times, i.e. on the fifth expiry of timer T300, the NW-TT shall abort the procedure.

6.3 Procedures for Bridge management service

6.3.1 TSN AF-requested Bridge management procedure

6.3.1.1 General

The purpose of the TSN AF-requested Bridge management procedure is to enable the TSN AF to:

a) obtain the list of bridge management parameters supported at the NW-TT;

b) obtain the current values of bridge management parameters at the NW-TT;

c) set the values of bridge management parameters at the NW-TT; or

d) subscribe to be notified by the NW-TT if the values of certain bridge management parameters change at the NW-TT;

e) unsubscribe to be notified by the NW-TT for one or more bridge management parameters; or

f) delete a bridge management parameter-entry at the NW-TT.

6.3.1.2 TSN AF-requested Bridge management procedure initiation

In order to initiate the TSN AF-requested Bridge management procedure, the TSN AF shall:

a) encode the information about the bridge management parameters values to be read, the bridge management parameters values to be set, the bridge management parameters changes to (un)subscribe to, the bridge management parameter-entry to be deleted and whether the TSN AF requests the list of bridge management parameters supported by the NW-TT in an Bridge management list IE as specified in clause 9.5B and include it in a MANAGE BRIDGE COMMAND message;

b) send the MANAGE BRIDGE COMMAND message to the NW-TT via the PCF and the SMF as specified in 3GPP TS 23.502 [3]; and

c) start timer T150 (see example in figure 6.3.1.2.1).

Figure 6.3.1.2.1: TSN AF-requested Bridge management procedure

6.3.1.3 TSN AF-requested Bridge management procedure completion

Upon receipt of the MANAGE BRIDGE COMMAND message, for each operation included in the Bridge management list IE, the NW-TT shall:

a) if the operation code is "get capabilities", include the list of Bridge management parameters supported by the NW-TT in the Bridge management capability IE of the MANAGE BRIDGE COMPLETE message;

b) if the operation code is "read parameter", attempt to read the value of the bridge management parameter at the NW-TT, and:

1) if the value of the parameter at the NW-TT is read successfully, include the parameter and its current value in the Bridge status IE of the MANAGE BRIDGE COMPLETE message; and

2) if the value of the parameter at the NW-TT was not read successfully, include the parameter and associated Bridge management service cause value in the Bridge status IE of the MANAGE BRIDGE COMPLETE message;

c) if the operation code is "set parameter", attempt to set the value of the bridge management parameter at the NW-TT to the value specified in the operation, and:

1) if the value of the parameter at the NW-TT is set successfully, include the parameter and its current value in the Bridge update result IE of the MANAGE BRIDGE COMPLETE message; and

2) if the value of the parameter at the NW-TT was not set successfully, include the parameter and associated Bridge management service cause value in the Bridge update result IE of the MANAGE BRIDGE COMPLETE message;

d) if the operation code is "subscribe-notify for parameter", store the request from the TSN AF to be notified of changes in the value of the corresponding bridge management parameter;

e) if the operation code is "unsubscribe for parameter", delete the stored request from the TSN AF to be notified of changes in the value of the corresponding bridge management parameter, if any;

f) if the operation code is "delete parameter-entry", attempt to delete the referred parameter-entry of the parameter at the NW-TT, and

1) if the parameter-entry of the parameter at the NW-TT is deleted successfully, include the parameter and its current value in the Bridge update result IE of the MANAGE BRIDGE COMPLETE message; and

2) if the parameter-entry of the parameter at the NW-TT was not deleted successfully, include the parameter and associated Bridge management service cause value in the Bridge update result IE of the MANAGE BRIDGE COMPLETE message; and

g) send the MANAGE BRIDGE COMPLETE to the TSN AF via the SMF and the PCF as specified in 3GPP TS 23.502 [3].

6.3.1.4 Abnormal cases in the TSN AF

The following abnormal cases can be identified:

a) T150 expired.

The TSN AF shall, on the first expiry of the timer T150, retransmit the MANAGE BRIDGE COMMAND message and shall reset and start timer T150. This retransmission is repeated four times, i.e. on the fifth expiry of timer T150, the TSN AF shall abort the procedure.

6.3.1.5 Abnormal cases in the NW-TT

The following abnormal cases can be identified:

a) Transmission failure of the MANAGE BRIDGE COMPLETE message indication from lower layers.

The NW-TT shall not diagnose an error and consider the TSN AF-initiated Bridge management procedure complete.

NOTE: Considering that the TSN AF-initiated Bridge management procedure complete as a result of this abnormal case does not cause the NW-TT to revert the execution of the operations included in the MANAGE BRIDGE COMMAND message.

6.3.2 NW-TT-initiated Bridge management procedure

6.3.2.1 General

The purpose of the NW-TT-initiated Bridge management procedure is to notify the TSN AF of one or more changes in the value of Bridge management parameters for which the TSN AF had requested to be notified of changes via the TSN AF-initiated Bridge management procedure.

6.3.2.2 NW-TT-initiated Bridge management procedure initiation

In order to initiate the NW-TT-initiated Bridge management procedure, the NW-TT shall create a BRIDGE MANAGEMENT NOTIFY message and shall:

a) include the Bridge management parameters to be reported to the TSN AF with their current value in the Bridge status IE of the BRIDGE MANAGEMENT NOTIFY message;

b) start timer T350; and

c) send the BRIDGE MANAGEMENT NOTIFY message to the TSN AF via the SMF and the PCF as specified in 3GPP TS 23.502 [3].

Figure 6.3.2.2.1: NW-TT-initiated Bridge management procedure

6.3.2.3 NW-TT-initiated Bridge management procedure completion

Upon receipt of the BRIDGE MANAGEMENT NOTIFY message, the TSN AF shall:

a) create a MANAGE BRIDGE MANAGEMENT NOTIFY ACK message; and

b) send the MANAGE BRIDGE MANAGEMENT NOTIFY ACK message to the NW-TT via the PCF and the SMF as specified in 3GPP TS 23.502 [3].

Upon receipt of the BRIDGE MANAGEMENT NOTIFY ACK message, the NW-TT shall stop timer T350.

6.3.2.4 Abnormal cases in the TSN AF

The following abnormal cases can be identified:

a) Transmission failure of the BRIDGE MANAGEMENT NOTIFY ACK indication from lower layers.

The TSN AF shall not diagnose an error and consider the NW-TT-initiated Bridge management procedure complete.

6.3.2.5 Abnormal cases in the NW-TT

The following abnormal cases can be identified:

a) T350 expired.

The NW-TT shall, on the first expiry of the timer T350, retransmit the BRIDGE MANAGEMENT NOTIFY message and shall reset and start timer T350. This retransmission is repeated four times, i.e. on the fifth expiry of timer T350, the NW-TT shall abort the procedure.

b) Transmission failure of the BRIDGE MANAGEMENT NOTIFY COMPLETE message indication from lower layers.

The NW-TT shall not diagnose an error and consider the NW-TT-initiated Bridge management procedure complete.