Page 21 - Cloud computing: From paradigm to operation

Framework and requirements for cloud computing 1

– Hybrid cloud: Cloud deployment model using at least two different cloud deployment models. The
deployments involved remain unique entities but are bound together by appropriate technology
that enables interoperability, data portability and application portability. A hybrid cloud may be
owned, managed, and operated by the organization itself or a third party and may exist on premises
or off premises. Hybrid clouds represent situations where interactions between two different
deployments may be needed but remained linked via appropriate technologies. As such the
boundaries set by a hybrid cloud reflect its two base deployments.

6.6 Cloud computing cross cutting aspects
Cross cutting aspects are behaviours or capabilities which need to be coordinated across roles and
implemented consistently in a cloud computing system. Such aspects may impact multiple roles, activities,
and components, in such a way that it is not possible to clearly assign them to individual roles or components,
and thus become shared issues across the roles, activities and components.
Key cross cutting aspects include:

– Auditability: The capability of collecting and making available necessary evidential information
related to the operation and use of a cloud service, for the purpose of conducting an audit;
– Availability: The property of being accessible and usable upon demand by an authorized entity. The
"authorized entity" is typically a cloud service customer;
– Governance: The system by which the provision and use of cloud services are directed and
controlled. Cloud governance is cited as a cross-cutting aspect because of the requirement for
transparency and the need to rationalize governance practices with SLAs and other contractual
elements of the cloud service customer to cloud service provider relationship. The term internal
cloud governance is used for the application of design-time and run-time policies to ensure that
cloud computing based solutions are designed and implemented, and cloud computing based
services are delivered, according to specified expectations. The term external cloud governance is
used for some form of agreement between the cloud service customer and the cloud service
provider concerning the use of cloud services by the cloud service customer;
– Interoperability: Ability of a cloud service customer to interact with a cloud service and exchange
information according to a prescribed method and obtain predictable results;
– Maintenance and versioning: Maintenance refers to changes to a cloud service or the resources it
uses in order to fix faults or in order to upgrade or extend capabilities for business reasons.
Versioning implies the appropriate labelling of a service so that it is clear to the cloud service
customer that a particular version is in use;
– Performance: A set of behaviours relating to the operation of a cloud service, and having metrics
defined in a SLA;
– Portability: Ability of cloud service customers to move their data or their applications between
multiple cloud service providers at low cost and with minimal disruption. The amount of cost and
disruption that is acceptable may vary based upon the type of cloud service that is being used;
– Protection of PII: Protect the assured, proper, and consistent collection, processing, communication,
use and disposal of Personally Identifiable Information (PII) in relation to cloud services;
– Regulatory: There are a number of different regulations that may influence the use and delivery of
cloud services. Statutory, regulatory, and legal requirements vary by market sector and jurisdiction,
and they can change the responsibilities of both cloud service customers and cloud service
providers. Compliance with such requirements is often related to governance and risk management
activities;
– Resiliency: Ability of a system to provide and maintain an acceptable level of service in the face of
faults (unintentional, intentional, or naturally caused) affecting normal operation;

13