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Framework and requirements for cloud computing 1

Table I.7 – A use case for cloud service cancellation
Title A use case for deregistration of cloud services
Description This use case assumes that cloud service deregistration is performed when the contract
between a CSP and a CSN: cloud service broker is cancelled during normal contract agreement.
The contract cancellation is out of scope and the abnormal situations such as bankruptcy and
service disruption of the CSP are not considered in this contribution.
Service deregistration can be done by the request from a CSP or a CSN: cloud service broker. A
CSP initiates deregistration of the cloud service for some internal situations (e.g., modification
or unavailability of the cloud service) during the cloud service. A CSN: cloud service broker can
also request to deregister the cloud service, e.g., violation of contract requirement by CSPs.
When the service deregistration is agreed with each other between a CSP and a CSN: cloud
service broker and it is confirmed, the CSN: cloud service broker stops the CSCs search and
selects the service targeted to be deregistered and stops posting the service list at the
workspace from the product catalogue.
The CSN: cloud service broker also investigates the CSCs that have contacted to use the service
and, if they exist, notifies deregistration of the service to the registered CSCs. When CSCs are
using the service currently, the CSN: cloud service broker requests the CSP to maintain the
service until the CSCs finish using the service. After that, the CSN: cloud service broker cancels
the contract corresponding to the cloud service between the CSN: cloud service broker and the
CSC and, if needed, renews the contract between them.
To complete the service deregistration, the CSN: cloud service broker can start the internal
process of deregistration. The CSN: cloud service broker deregisters the service on a product
catalogue and invalidates all related information such as monitoring, metering, CSC's account,
SLA, etc. CSP's APIs that allow the CSC to interact with the CSP are also disabled so as not to
access the service any more. The CSN: cloud service broker finally notifies the CSP
deregistration that the cloud service is completed.
Roles/sub-roles CSP, CSN: cloud service broker, CSC
Figure

Pre-conditions A CSP registered a cloud service to the list of a product catalogue in a CSN: cloud service
(optional) broker.
A CSC signed a contract with a CSN: cloud service broker for cloud service.
Post-conditions A CSC cannot search the cloud services on product catalogue and cannot use the cloud
(optional) service.

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