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IT3223. Chapter Standards. Why Standards?. Characteristics Organizational processes Profiles. What is a Standard?. Public document Defines specification Complete, precise, verifiable Requirements Design Characteristics Maintained by group consensus. Computer System Standard.
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IT3223 Chapter Standards
Why Standards? • Characteristics • Organizational processes • Profiles
What is a Standard? • Public document • Defines specification • Complete, precise, verifiable • Requirements • Design • Characteristics • Maintained by group consensus
Computer System Standard • Specification Defines • Interface • Service • Processes • Protocols • Data formats • Maintained by group consensus
Profile • Set of one of more standards to accomplish particular function
Standards • de facto • Specification for particular product that emerges due to product’s popular use • May be linked to single vendor • de jure • Specification created by accredited standards development organization • Goals: • Broad availability of products • Competition • Lower prices
Standards Organizations • How standards developed? • Differences among standards • Government • Industry • Trend in 1990’s for government to adopt industry standards instead of creating
Top 10 NonGov’t US Standard Developers • ASTM • US Pharmacopeia • SAE • AIA • AOAC • ANSI • EIA • Amer. Assoc State hwy and Trans Officials • Cosmetic, Toiletry and Fragrance
Influential Standard Organizations • ISO • ANSI
Influential Standard Organizations • ISO • Worldwide standards • Facilitate international exchange of goods & services • Develop cooperation • Intellectual • Scientific • Technical • Economic
Influential Standard Organizations • ANSI • Private • Nonprofit • US representative of ISO • Promotes voluntary consensus • Protects integrity of standards development process • No official government charter • Open to manufacturers, organizations, users, communication carriers • 13000 approved ANSI standards • Developed by member organizations • Coordinates work • Certifies standards developed according to accredited procedures • Does not judge standards
Standards Organization Categories • Accredited • Approved by international standards organization such as ISO or ANSI • Define and publish public standards • Non accredited • Consortia, private organizations, vendor: de facto • Define and publish group standards
Consensus Processes • Group consensus used to develop standard • Multiple people or organizations • Process in which consensus achieved • Developer accredited
Typical Formal Process • Submit project authorization request • Obtain approval for request • Organize working group • Develop draft standard • Vote on draft standard • Approve draft standard • Publish approved standard • Forward to international standardization
Other processes • Change requests • Interpretation of standard • Review of standard for update or removal
Standard Approval • Balance working group • Producers • Users • General interest participants • Ballot process outside of working group
Facets of Consensus • Participation • Development and approval process • Post approval process to monitor changes to existing standards • Willingness of organization to accept and vote on standards developed by affiliate groups
Consensus Processes • Impacted by type of organization • Membership may be limited • Level of agreement necessary for approval • Appeal available? • More time needed for formal process and larger consensus group • More complex with formal process and larger consensus group • Formal process more predictable and stable
Standard Changes • Corrections • Clarifications/interpretation of existing functionality • New, modified functionality • Process of change impacted by type of organization and scale of process • Some organizations require review/reaffirmation of standards at stated intervals ( ballot )
Standard Stability • Accredited generally more stable • Must consider compatibility of change to prior standard implementation
Characteristics of Standards • Types of information • Normative • Prescribes requirements, specifications • Requirements may be mandatory or optional • Optional features may impact interoperability • Optional features must conform to standard • Some specifications may be implementation defined • Informative • Discloses instructive information – not requirements • Examples, tutorial, guidance
Standards Maturity • Stability • State of development and approval • Degree of acceptance in the marketplace • Age – issues identified and cleaned up • Technology can render standards obsolete
Approval States • Approved • Draft • Cancelled
Profiles • Developed from one or more base standards • Allows inclusion of different types and sources of standards • Defines mandatory parts of standards and included optional parts • Requires thorough understanding of standards
Value of Profiles • Document appropriate standards • Document relationships among them • Visibility • Gaps • Overlaps • Inconsistencies • Incompatibilities • Document how products using standards should work together
Profile Characteristics • Satisfies all functional requirements • Satisfies all logical requirements • Provides sufficient detail for implementation • Provides sufficient detail for conformance testing
Profile Issues • ID potential for variations as implemented • Classification schemes • Adding functionality to profile • Coherence among standards in profile • Overlap confusion of standards • Conformance to standard vs conformance to profile
Conformance • Relationship of standard to implementation • Strict ( no additional features ) • With extensions
Conformance • Specify • Conformance statements • Test assertions • Verify • Testing using standard test suites • Reference implementations • Conformance demonstrations
Break Out • You need to develop policy for the webct replacement project regarding use of vendor extensions. • What are you concerned about? • What do you think policy should be? • What impact does the marketplace have on your policy?