Content for &nbsp; TS 23.542 &nbsp; Word version:&nbsp; 18.4.0

The PIN Gateway Client or the PIN Client sends a PIN Management PEGC Service Continuity request to the PIN Management Client for a specific service. The PIN Management PEGC Service Continuity request includes security credentials, PIN Client identifier(s), PIN Gateway identifier, and Service identifier.

Upon receiving the request, the PIN Management Client validates the request and checks if the request is authorized for the given PIN Client(s), PIN Gateway Client and service. If the request is authorized and valid, the PIN Management Client determines if a target PIN Gateway Client meets the requirements for handling the application traffic for the provided service.

If the PIN Management Client identifes a target PIN Gateway Client that meets the requirements, the PIN Management Client sends PIN Management PEGC Configuration request to the target PIN Gateway Client to configure the target PIN Gateway for handling service traffic from the PIN Client(s) as in clause 8.9.2.1.3. If the service is provided by an Application Server, the PIN Management Client send a PIN Configuration Service Continuity Update request to the PIN Server if needed to inform of the service continuity changes in the PIN as in clause 8.9.2.1.4.

Figure 8.9.2.1.3-1: PIN Management PEGC Configuration procedure

If the procesing of the request was successful, the PIN Management Client sends a PIN Management PEGC Service Continuity response to indicate that the request processing was successfull and includes target PIN Gateway Client information. Otherwise, the PIN Management Client sends a PIN PEGC Service Continuity response indicating that the request processing failed and can include appropriate reasons.

Upon receiving the PIN Management PEGC Service Continuity response, if the response was received by the PIN Client, the PIN Client validates if the request was successful and can inform the application client of the target PIN Gateway Client provided in the response to establish connectivity. If the response was received by the PIN Gateway Client, the PIN Gateway Client notifies each PIN Client included in the PIN Management PEGC Service Continuity request about the target PIN Gateway Client change as in clause 8.9.2.1.5.

8.9.2.1.3 PIN Management PEGC Configuration procedure p. 113

Pre-conditions:

The PIN Management Client has received a PIN Management PEGC Service Continuity request; and
The PIN Management client has identified a target PIN Gateway Client.

Reproduction of 3GPP TS 23.542, Fig. 8.9.2.1.3-1: PIN Management PEGC Configuration procedure

The PIN Management Client sends a PIN Management PEGC Configuration request to the target PIN Gateway Client. The PIN Management PEGC Configuration request includes security credentials, PIN Client identifier(s), PIN Gateway identifier, and Service identifier.

Upon receiving the request, the PIN Gateway Client validates the request and checks if the PIN Management Client is authorized to request PEGC Configuration. If the request is authorized and the request is valid, the PIN Gateway Client creates a new configuration for the PIN Client(s) and service that are indicated in the request.

Figure 8.9.2.1.4-1: PIN Configuration Service Continuity Update procedure

If the processing of the request was successful, the target PIN Gateway Client sends a PIN Management PEGC Configuration response to the PIN Management Client to indicate that the request was successful and can include connectivity information to be used by the PIN Client(s). Otherwise, the target PIN Gateway sends a PIN Management PEGC Configuration response indicating that the request failed and can include appropriate reasons.

Upon receiving the PIN Management PEGC Configuration response, the PIN Management Client uses the information provided in the response to inform the PIN Client(s) or the PIN Gateway Client from which the service continuity request originated as in clause 8.9.2.1.2.

8.9.2.1.4 PIN Configuration Service Continuity Update procedure p. 114

The PIN Configuration Service Continuity Update procedure allows the PEMC to inform the PIN Server about a service continuity request received at the PEMC for a PINE, and it allows the PIN Server to inform the related AS of the same if such functionality is supported by the AS.

The PIN Server may provide, in the response, policy information to the PEMC about service continuity for the concerned PINE.

Pre-conditions:

PINE has an application session that goes through a PEGC; and
PEGC needs to be replaced (e.g., PEGC will become unavailable or PEGC is unreachable).
The AS is successfully subscribed for PIN service continuity notifications with the PIN Server.

Reproduction of 3GPP TS 23.542, Fig. 8.9.2.1.4-1: PIN Configuration Service Continuity Update procedure

The PEMC sends a PIN Configuration Service Continuity Update request to the PIN Server. The PIN Configuration Service Continuity Update request includes the requestor identifier, security credentials, PINE identifier(s), source and target PIN Gateway identifiers, and service identifier (e.g., application client identifier, application server identifier, application session identifier, application session identifier), and the PIN ID.

Upon receiving the request, the PIN Server validates the request and checks if the PEMC is authorized to request service continuity update. If the request is authorized and valid, if the PIN Server has not authorized the PINE for service continuity, the PIN Server validates if the PINE is authorized and determines policy information about service continuity for the PINE. If the PIN Server has already authorized the PINE for service continuity, the PIN Server updates the configuration for the PINE and service indicated in the request.

Figure 8.9.2.1.5-1: PIN Management PEGC Discovery procedure

If the PIN Server needs to update the AS with service continuity information, the PIN Server sends a PIN Service Continuity notification to the AS. The PIN Service Continuity notification includes PIN identifier, PINE identifier(s), PEGC identifier, service identifier and may include an application session identifier and terminating endpoints on the PINE and PEGC.

Step 4.

Upon receiving the notification, the AS validates the notification. If the notification is valid, the AS updates the service continuity configuration related to the PINE and service indicated in the notification.

Step 5.

If the processing of the PIN Configuration Service Continuity Update request was successful, the PIN Server sends a PIN Configuration Service Continuity Update response to indicate that the request processing was successful and may include policy information about service continuity for the PINE. Otherwise, the PIN Server sends a PIN Configuration Service Continuity Update response indicating that the request processing failed and can include appropriate reasons.

Upon receiving the PIN Configuration Service Continuity Update response, the PEMC uses the information provided in the response to inform the PINE(s) or the PEGC from which the service continuity request originated as in clause 8.9.2.1.2.

8.9.2.1.5 PIN Management PEGC Discovery procedure p. 115

PEMC performs PIN Management PEGC discovery procedure to discover which PEGC are available at the PINE when the PEMC does not have that information; for example, the PEMC may ignore if a PEGC is available at the PINE or PEGC information may not have been provided to the PEMC in the service provisioning request.

Pre-conditions:

The PEMC has been triggered for service continuity;
The target PEGC is not known by the PEMC.

Reproduction of 3GPP TS 23.542, Fig. 8.9.2.1.5-1: PIN Management PEGC Discovery procedure

The PEMC sends a PIN Management PEGC Discovery request to the PINE involved in the service continuity procedure. The PIN Management PEGC Discovery request includes security credentials, requestor identifier, PIN identifier, PINE identifier and list of PEGC information.

Upon receiving the request, the PINE validates the request and checks if the request is authorized. If the request is authorized and valid, the PINE uses the PEGC information provided in the request to identify PEGC(s) that are reachable and creates a list of PEGC identifier(s) that are available at the PINE.

Figure 8.9.2.1.6.2.1-1: PIN service continuity subscribe

If the procesing of the request was successful, the PINE sends a PIN Management PEGC Discovery response to indicate that the request processing is successfull and includes the list of PEGC identifier(s) available at the PINE. Otherwise, the PINE sends a PIN Management PEGC Discovery response indicating that the request processing failed and can include appropriate reasons.

Upon receiving the response, the PEMC selects the target PEGC based on the list of available PEGC received and the PIN policy.

8.9.2.1.6 PIN Service Continuity subscription p. 116

8.9.2.1.6.1 General p. 116

The PIN service continuity subscription is used by the Application Server to be notified of PIN service continuity events by the PIN Server.

The PIN service continuity notification includes PIN service continuity information.

8.9.2.1.6.2 Procedure p. 116

8.9.2.1.6.2.1 PIN service continuity subscribe p. 116

Figure 8.9.2.1.6.2.1-1 illustrates the PIN service continuity subscribe procedure.

Pre-conditions:

The application server has already received the address of the PIN server;
The application server is authorized to communicate with PIN server;

The application server sends the PIN service continuity subscribe request to the PIN server. The PIN service continuity subscribe request includes the application server identifier along with the security credentials, PIN ID, subscribed event, notification target address and proposed expiration time.

Upon receiving the request from the application server, the PIN server checks if the application server is authorized to subscribe. The authorization check may apply to an individual PIN. If the request is authorized, the PIN server creates and stores the subscription for application server.

Figure 8.9.2.1.6.2.2-1: PIN service continuity notify procedure

If the processing of the request is successful, the PIN server sends a PIN service continuity subscribe response to the application server, which includes the subscription identifier and may include the expiration time, indicating when the subscription will automatically expire. To maintain the subscription, the application server shall send a PIN service continuity update request prior to the expiration time. If a new PIN service continuity update request is not received prior to the expiration time, the PIN server shall treat the application server as implicitly unsubscribed.

8.9.2.1.6.2.2 PIN service continuity notify p. 116

Figure 8.9.2.1.6.2.2-1 illustrates the PIN service continuity notify procedure.

Pre-conditions:

The application server has subscribed with the PIN server as specified in clause 8.9.2.1.6.2.1.

Reproduction of 3GPP TS 23.542, Fig. 8.9.2.1.6.2.2-1: PIN service continuity notify procedure

When a service continuity event occurs at the PIN server that satisfies triggering conditions, the PIN server sends a service continuity notification to the subscribed application servers.

The PIN server sends an PIN service continuity notification to the subscribed application server(s) related to the service continuity event and includes the PIN service continuity information.

The PIN service continuity information includes the PIN subscription identifier, subscribed event, PIN server identifier, PIN identifier, PINE identifier(s), PEGC identifier, service identifier, application session identifier and may include terminating endpoints on the PINE and PEGC.

Figure 8.9.2.1.6.2.3-1: PIN service continuity update

Upon receiving the notification, the application server uses the information provided in the notification to update the service continuity configuration related to the PINE and service indicated in the notification.

8.9.2.1.6.2.3 PIN service continuity update p. 117

Figure 8.9.2.1.6.2.3-1 illustrates the PIN service continuity update procedure.

Pre-conditions:

The application server has subscribed with the PIN server as specified in clause 8.9.2.1.6.2.1.

Reproduction of 3GPP TS 23.542, Fig. 8.9.2.1.6.2.3-1: PIN service continuity update

The application server sends a PIN service continuity update request to the PIN server. The PIN service continuity update request includes the security credentials and the subscription identifier. It may also include notification target address, PIN ID, event ID and proposed expiration time.

Upon receiving the request from the application server, the PIN server checks if the application server is authorized to update the subscription information. If the request is authorized, the PIN server updates the stored subscription.

Figure 8.9.2.1.6.2.4-1: PIN service continuity unsubscribe

If the processing of the request is successful, the PIN server sends a PIN service continuity update response to the application server, which may include the expiration time, indicating when the subscription will automatically expire. To maintain the subscription, the application server shall send a PIN service continuity update request prior to the expiration time. If a PIN service continuity update request is not received prior to the expiration time, the PIN server shall treat the application server as implicitly unsubscribed.

8.9.2.1.6.2.4 PIN service continuity unsubscribe p. 118

Figure 8.9.2.1.6.2.4-1 illustrates the PIN service continuity unsubscribe procedure.

Pre-conditions:

The application server has subscribed with the PIN server as specified in clause 8.9.2.1.6.2.1.

Reproduction of 3GPP TS 23.542, Fig. 8.9.2.1.6.2.4-1: PIN service continuity unsubscribe

The application server sends a PIN service continuity unsubscribe request to the PIN server. The PIN service continuity unsubscribe request includes the security credentials and the subscription identifier.

Upon receiving the request from the application server, the PIN server checks if the application server is authorized to unsubscribe. If the request is authorized, the PIN server cancels the subscription indicated by the subscription identifier.

Figure 8.9.2.2-1: Change application layer communication to communication via 5GS

If the processing of the request is successful, the PIN server sends a PIN service continuity unsubscribe response to the application server.

8.9.2.2 Service continuity in changing access to 5GS p. 118

This procedure solves the situation, that PINE 1 has application layer communication with PINE 2 via PEGC 1. But when the communication via PEGC 1 is not viable, for example, the PINE 2 moves out of the coverage of PEGC 1, only PINE 2 triggers to establish the 5GS communication to connect to PINE 1 via PEGC 2is the potential way.

Figure 8.9.2.2-1 illustrates the service continuity to change application layer communication via PEGC only to application layer communication via PEGC + 5GS or 5GS + PEGC based on request/response model.

Pre-conditions:

The PEMC in a PIN has been pre-configured or has discovered the address (e.g. IP address, FQDN, URI) of the PIN server;
The PIN has already been created and a PIN ID is distributed by PIN server;
The PINE 1 has the subscription that can communicate with PINE 2 via 5GS;
The PINE 2 does not have the 3GPP capability and require support of a PEGC to access the 3GPP network.

Reproduction of 3GPP TS 23.542, Fig. 8.9.2.2-1: Change application layer communication to communication via 5GS

The PINE 1 has application layer communication with PINE 2 via PEGC 1.

The PINE 2 moves out of PEGC 1 and moves into the coverage of PEGC 2. The PINE 2 connects to the network that provided by PEGC 2 via access control information.