Figure 10.3.3-1 below illustrates the group creation operations by authorized VAL user/UE/administrator to create a group. It applies to the scenario of normal group creation by a VAL administrator or by authorized user/UE.
The group management client, group management server, VAL server and the VAL group members belong to the same VAL system.
The authorized VAL user/UE/administrator is aware of the users' identities which will be combined to form the VAL group.
The group management client of the authorized VAL user/UE/administrator requests group create operation to the group management server. The identities of the users or UEs being combined and the information of the VAL services that are enabled on the group shall be included in this message.
During the group creation, the group management server creates and stores the information of the group. The group management server performs the check on the policies e.g. maximum limit of the total number of VAL group members for the VAL group(s). The external group identifier, identifying the member UEs of the VAL group at the 3GPP core network, is stored in the newly created VAL group's configuration information.
The group management client of the VAL user/UE requests the group information on the VAL group from the group management server by sending a group information query request. The query type is included.
The group management server checks whether the VAL user/UE is authorized to perform the query. If authorized, then the group management server retrieves the requested group information based on the query type.
Figure 10.3.5.1-1 illustrates the group membership notification operations to the VAL server(s) and group management clients upon the group membership change at group management server.
VAL group is created on the group management server.
The group management client requests to retrieve the relevant group configurations from group management server, if the user or UE is added to the group. If the user or UE is deleted from the group, the locally stored group configurations in the VAL UE may be removed.
Figure 10.3.5.2-1 below illustrates the group membership update operations by an authorized user/UE/administrator/VAL server to change the membership of a VAL group (e.g. to add or delete group members).
The group management server and VAL server serve the same VAL system;
The initiator of this operation is aware of the current group membership of the VAL group;
The authorized user/UE/administrator/VAL server is aware of the users' identities which will be added to or deleted from the VAL group.
The group management server provides a store group configuration response indicating success or failure. If any validation or storage fails, the group management server provides a failure indication in the store group configuration response.
The procedure for retrieve group configurations at the group management client or the VAL server is described in Figure 10.3.6.2-1. This procedure can be used following service authorisation when the configuration management client has received the list of groups and the group management client needs to obtain the group configurations, or following a notification from the group management server that new group configuration information is available.
The group management server has received configuration data for groups, and has stored this configuration data;
The VAL UE has registered for service and the group management client or the VAL server needs to download group configuration data applicable to the user/UE.
The procedure for subscription for group configuration data as described in Figure 10.3.6.3-1 is used by the group management client to indicate to the group management server that it wishes to receive updates of group configuration data for groups for which it is authorized.
The group management server has some group configurations stored.
The group management server provides a subscribe group configuration response to the group management client indicating success or failure of the request.
The procedure for notification of group configuration data as described in Figure 10.3.6.3-2 is used by the group management server to inform the group management client that new group configuration data is available. It can also be used by the group management server to provide new group related key material to the group management client.
The group management client has subscribed to the group configuration information
The group management server has received and stored new group configuration information, or the group management server has generated and stored new key material, or both of these have occurred.
The group management server provides the notification to the group management client, who previously subscribed for the group configuration information. Optionally, the notify group configuration request may contain group related key material for the group management client.
If the group management server had provided group related key material to the group management client, the group management client stores the key material.
If the group management server has notified the group management client about new group configuration information through this procedure, the group management client may then follow the procedure described in subclause 10.3.6.2 in order to retrieve that group configuration information.