Actor: User Application

Goal: Leave Peer Group

Description: Allows an application to leave a previously joined group

Preconditions:

1. The engine must be started.
2. The engine must be a member of the group the application is leaving.

1. The engine is no longer a member of the joined group.

Related Use Cases:

UC11.0 - Join Peer Group
UC13.0 - Create Peer Group
UC14.0 - Delete Peer Group

Notes and Issues:

None

Event Flow:

1. The application requests the engine to leave a group.
2. The engine sends a request to leave a group.
3. The engine receives a response that the request to leave the group succeeded.
4. The engine removes the group from its internal list of joined groups.
5. The engine informs the application that the leave succeeded.

UC12.1 Engine is not started

1. The application requests the engine to leave a group.
2. The engine returns an error that the it has not been started.

UC12.2 Not a member of the group

1. The application requests the engine to leave a group.
2. The engine sends a request to leave a group.
3. The engine receives a response that the request to leave the group failed.
4. The engine informs the application that the leave failed due to lack of membership.

UC12.3 Group not found

1. The application requests the engine to leave a group.
2. The engine sends a request to leave a group.
3. The engine receives a response that the request to leave the group failed.
4. The engine informs the application that the join failed due to an invalid group.

Sequence Diagrams:

Revision History

Name	Date	Reason for Change	Version