Page 174 - Cloud computing: From paradigm to operation

1 Framework and requirements for cloud computing

Table I.10 – A use case of cloud service control status validation
Title A use case for cloud service control status validation in cloud service brokerage.

Description This use case describes a validation of legitimate service status after a CSN: cloud service
broker made a request for an action (e.g., create, pause, resume, or restart) to change service
status on behalf of a CSC. Since a CSP and a CSN: cloud service broker are not tightly coupled,
the CSN: cloud service broker does not know the result of the control request instantly. So, a
CSN: cloud service broker needs to keep checking status of service by communicating with the
CSP until the CSN: cloud service broker verifies whether the control request is correctly
performed or not.
(1) On behalf of the CSC, the CSN: cloud service broker makes a control request (e.g., create,
pause, resume, restart, or terminate) to the CSP who is hosting the service.
(2) The requested CSP sends an acknowledgement to the CSN: cloud service broker for the
service control request and starts to control a service accordingly.
(3) After the CSN: cloud service broker receives the acknowledgement, the CSN: cloud
service broker sets a time window to wait and periodically verify the service status. The
CSN: cloud service determines an efficient period to repeat a communication with the
CSP to get information on the latest service status.
(4) The CSN: cloud service broker verifies that the current service status complies with the
ideal service status by the request from the CSC. The CSN: cloud service broker keeps
communicating with the CSP until the service status becomes ideal status or error status,
or a certain deadline is over.
(5) Finally, through the workspace, the CSN: cloud service broker notifies the result of service
control to the CSC.

Roles/sub-roles CSP, CSN: cloud service broker, CSC
Figure

Pre-conditions The CSP has an account for accessing CSB workspace.
(optional) The CSC has an account for accessing CSB workspace.
The CSC selected a cloud service to utilize.
CSN: cloud service broker and CSC established a SLA.

166