Integrity
The concept of cloud information integrityrequires that the following three
principles are met:
Modifications are not made to data by unauthorized personnel or processes.
Unauthorized modifications are not made to data by authorized personnel or processes.
The data is internally and externally consistent — in other words, the
internal information is consistent both among all sub-entities and with
the real-world, external situation.
Availability
Availabilityensures the reliable and timely access to cloud data or cloud computing resources by the appropriate personnel. Availability guarantees that
the systems are functioning properly when needed. In addition, this concept
guarantees that the security services of the cloud system are in working order.
A denial-of-service attack is an example of a threat against availability.
The reverse of confidentiality, integrity, and availability is disclosure, alteration, and destruction (DAD).
Cloud Security Services
Additional factors that directly affect cloud software assurance include authentication, authorization, auditing, and accountability, as summarized in the
following sections.
Authentication
Authenticationis the testing or reconciliation of evidence of a user’s identity. It
establishes the user’s identity and ensures that users are who they claim to be.
For example, a user presents an identity (user ID) to a computer login screen and
then has to provide a password. The computer system authenticates the user by
verifying that the password corresponds to the individual presenting the ID.
Authorization
Authorizationrefers to rights and privileges granted to an individual or process
that enable access to computer resources and information assets. Once a user’s
Chapter 3 Cloud Computing Software Security Fundamentals 65
identity and authentication are established, authorization levels determine the
extent of system rights a user can hold.
Auditing
To maintain operational assurance, organizations use two basic methods: system
audits and monitoring. These methods can be employed by the cloud customer,
the cloud provider, or both, depending on asset architecture and deployment.
A system auditis a one-time or periodic event to evaluate security.
Monitoringrefers to an ongoing activity that examines either the system
or the users, such as intrusion detection.
Information technology (IT) auditors are often divided into two types: internal
and external. Internal auditors typically work for a given organization, whereas
external auditors do not. External auditors are often certified public accountants
(CPAs) or other audit professionals who are hired to perform an independent
audit of an organization’s financial statements. Internal auditors usually have a
much broader mandate than external auditors, such as checking for compliance
and standards of due care, auditing operational cost efficiencies, and recommending the appropriate controls.
IT auditors typically audit the following functions:
System and transaction controls
Systems development standards
Backup controls
Data library procedures
Data center security
Contingency plans
In addition, IT auditors might recommend improvements to controls, and
they often participate in a system’s development process to help an organization
avoid costly reengineering after the system’s implementation.
An audit trail or logis a set of records that collectively provide documentary
evidence of processing, used to aid in tracing from original transactions forward
to related records and reports, and/or backward from records and reports to
their component source transactions. Audit trails may be limited to specific
events or they may encompass all of the activities on a system.
Audit logs should record the following:
The transaction’s date and time
đang được dịch, vui lòng đợi..
