Content for  TS 23.558  Word version:  19.3.0

The EEC sends EEC registration request to the EES. The request from the client includes the security credentials received after successful authorization for edge computing services and may include a proposed expiration time. The request also optionally includes information indicating to the EES how the EEC expects to use the services of the EES. The EEC may include indication for UE mobility support requirement to the EES. If the EEC is moving to this EES from the purview of another EES, called S-EES, the request from the EEC may include the identity and endpoint of the S-EES and an EEC context ID that was provided by the S-EES to maintain continuity of the EEC context and to authorize EEC context relocation. If the EEC registration is being performed as part of ACR, the EEC shall not include the S-EES endpoint and the EEC context ID.

Upon receiving the request from the EEC, the EES validates the registration request and verifies the security credentials. The EES further determines whether the requirements that were indicated in the AC Profile(s) can be fulfilled e.g., without failing to meet the requirements of the already registered EECs, and reserves corresponding resources (e.g., for EASs). If the AC Profile(s) include EAS bundle information the reserved EAS resources are apportioned among the EASs in the bundle, based on the indicated requirements and local policies. If the EEC provides in the registration request the EAS selection request indicator and based on EES local policies, the EES selects EASs providing the capabilities required by the AC Profile(s), reserves the corresponding resources, and provides the information to the EEC in the registration response. If bundle EAS information (either as EAS bundle identifier or as a list of EASIDs) is included and the EAS selection request indicator is set, then the EES determines whether all or a subset of the EAS(s) in the bundle are registered and instantiated. If only a subset of bundle EASs is found, the EES may determine whether instantiable but not yet instantiated EASs match the subset of remaining (i.e. not yet found) bundle EASs and performs the dynamic EAS instantiation triggering procedure in clause 8.12 for this subset. If the EEC provides in the registration request a UE type, the EES may use this information to apply UE-type-specific local policies.

Upon successful validation of the request, if the received EEC registration request contains an EEC context ID and a S-EES Endpoint, the EES performs an EEC Context Pull relocation (clause 8.9.2.2) from the S-EES. The source and target EES perform EEC Context handling as detailed in clause 8.9.1. If the EEC registration request fails after the EEC Context Pull relocation, e.g., the EES cannot reserve the necessary resources while meeting the capability requirements of the existing registered EECs, the EES shall determine the EEC Context information stale and send a failure response with a corresponding cause.

The EES sends a successful EEC registration response, which includes the registration ID and may include a newly assigned EEC context ID. If the EEC registration request contains AC Profile(s), and the EES determines that the requirements indicated in the AC profile(s) cannot be fulfilled for some of the AC profile(s), the EES shall include the list of ACIDs of such AC Profile(s) and may include appropriate reasons. If step 3 was executed, the EEC registration response also includes EEC context retrieval result. The EEC stores the new EEC context ID and uses it if and when it registers with another EES. The EES may also provide an expiration time to indicate to the EEC when the registration will automatically expire. To maintain the registration, the EEC shall send a registration update request prior to the expiration. If a registration update request is not received prior to the expiration time, the EES shall treat the EEC as implicitly de-registered. If the EEC context relocation status indicates that the EEC context relocation was not successful, then the EEC performs the required EDGE-1 subscriptions at the T-EES.

The EEC sends EEC registration update request to the EES. The request from the client includes the security credentials received after successful authorization for edge computing services and may include a proposed expiration time and AC profile(s) parameters, including new or updated selected EAS information. The EEC may include indication for UE mobility support requirement to the EES.

Upon receiving the request from the EEC, the EES validates the registration update request and verifies the security credentials.

Upon successful validation of the request, the EES sends a successful registration update response, which may include updated expiration time to indicate to the EEC when the updated registration will automatically expire. If the EEC registration update request contains AC Profile(s), and the EES determines that the requirements indicated in the AC profile(s) cannot be fulfilled for some of the AC profile(s), the EES shall include the list of ACIDs of such AC Profile(s) and may include appropriate reasons. To maintain the registration, the EEC shall send a registration update request prior to the expiration time. If a registration update request is not received prior to the expiration time, the EES shall treat the EEC as implicitly de-registered.

The EEC sends EEC de-registration request to the EES. The request from the client includes the security credentials received after successful authorization for edge computing services.

Upon receiving the request from the EEC, the EES validates the de-registration request and verifies the security credentials.

Upon successful authorization, the EES sends a successful de-registration response.