Explanation: Acceptance confirms that users’ needs have been met by the supplied solution. Verification and Validation informs Acceptance by establishing the evidence – set against acceptance criteria - to determine if the solution meets the users’ needs. Acceptance should also explicitly address any integration or interoperability requirements involving other equipment or systems. To enable acceptance every user and system requirement must have a 'testable' characteristic.
Accreditation is the formal acceptance of security, adequacy, authorization for operation and acceptance of existing risk. Accreditation is the formal declaration by a Designated Approving Authority (DAA) that an IS is approved to operate in a particular security mode using a prescribed set of safeguards to an acceptable level of risk.
Certification is the formal testing of security safeguards and assurance is the degree of confidence that the implemented security measures work as intended. The certification is a Comprehensive evaluation of the technical and nontechnical security features of an IS and other safeguards, made in support of the accreditation process, to establish the extent to which a particular design and implementation meets a set of specified ecurity requirements.
Assurance is the descriptions of the measures taken during development and evaluation of the product to assure compliance with the claimed security functionality. For example, an evaluation may require that all source code is kept in a change management system, or that full functional testing is performed. The Common Criteria provides a catalogue of these, and the requirements may vary from one evaluation to the next. The requirements for particular targets or types of products are documented in the Security Targets (ST) and Protection Profiles (PP), respectively.
Source: ROTHKE, Ben, CISSP CBK Review presentation on domain 4, August 1999.
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Official ISC2 Guide to the CISSP CBK, Second Edition, on page 211.
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http://www.aof.mod.uk/aofcontent/tactical/randa/content/randaintroduction.htm