IV&Vs
“IV&V”, “Independent Verification and Validation”, or simply “A Second Pair of Eyes”. Whatever you call it, sometimes you need a new expert to check something your regular experts did for you. Not that you don’t trust them, not that you think they don’t know their stuff – simply that too much will depend on some work products to use them without checking them. For example, in an XML environment, the vocabulary or tag set and its expression as a schema are critical to the success of the entire application. After investing in selection and customization, or development, of a tag set, you may want a second pair of eyes on it before implementing a system based on it.
Schema IV&V
There are many ways to model any given set of data, and each of the XML schema languages – DTDs, W3C XML schemas, and a variety of other specification languages for denoting the structure and content of XML documents – has specific strengths. Developers must balance complex and often conflicting requirements. Just as it is often difficult to proofread one’s own work, it can be difficult for developers to identify the weaknesses and biases in schemas they construct. An independent audit can identify inconsistencies or weaknesses in schemas before applications are developed using them. Early detection and correction leads to a better finished product with reduced lag time and long-range costs.
Based on a client’s needs, Mulberry Technologies, Inc., can perform several different levels of Independent Validation and Verification (IV&V) for XML schemas. We can report on the fit between the schema implementation and the application; provide detailed analysis, tagged samples, comparison to industry schemas, modularity evaluation, and analysis of character sets; and render similar services according to your need.
Our report can take the form of an analytical white paper, code, or both.
Evaluating an XML Schema
When Mulberry performs an XML schema IV&V, we evaluate the schema itself, the documentation accompanying it, and (to the extent it is documented) the analysis on which the schema is based. We:
- Analyze and test the schema, and produce a report listing any inconsistencies, deficiencies, or suggested improvements. Included in this analysis are evaluations of the schema’s:
- modularity
- flexibility
- extensibility
- Assess the schema for appropriate use of data typing
- Critique the use of element typing and grouping
- Review the schema’s use of associated specifications, such as XLink and Namespaces
- Evaluate the immediate and long-term purposes of the XML application, the user community for whom the schema was written, and the functions your XML is intended to perform
- Critique the quality of documentation for users uncomfortable reading a schema, e.g., the tagging scheme, definitions, and explanations which do not fit within the schema’s limited syntax
Mulberry’s technical quality review can include such factors as design efficiency, internal consistency, and correct use of constructs. We can assess the overall quality of the DTD or schema suite, including formatting, adequacy of both modeling and documentation, use of a consistent internal naming convention, and intangibles such as clarity, logic, and elegance. Based on our analysis, we describe any observed analysis or modeling irregularities, recommend immediate solutions to simple problems, and may suggest alternative approaches to major problems.
XSLT IV&V
While XSLT stylesheets and transformations can be simple and elegant pieces of work, in real-world applications, XSLT can often be complex and lengthy. Good XSLT transformations, whether targeting HTML, XSL-FO, or some other format, are based on a sound understanding of XSL’s processing model as well as the source data structure and constraints, and the requirements for processing. Well-designed stylesheets run better and are easier to maintain, reuse, and integrate.
When building XSLT stylesheets, developers must deal with often conflicting and complex requirements. An independent audit serves as the “proofread” to identify any weaknesses and inconsistencies in stylesheet construction ... before applications are developed using the stylesheets. Early detection and correction leads to a better finished product with reduced lag time and long-range costs.
Based on a client’s needs, Mulberry Technologies, Inc., can perform several different levels of Independent Validation and Verification (IV&V) on XSLT stylesheets. We can test on a range of inputs and analyze stylesheets at detailed and high levels, considering process flow, efficiencies, code reuse, and modularization.
Our report can take the form of an analytical white paper, XSLT code, or both.
Evaluating an XSLT Stylesheet
When Mulberry performs an XSLT IV&V, the stylesheet is evaluated against the baseline DTD or schema and the DTDs or schemas into which it is being transformed, as well as sample instances. Specifically, Mulberry evaluates the stylesheet for:
- Effectiveness: Does the stylesheet perform as intended?
- Robustness: Will the stylesheet accommodate reasonable variations in data?
- Maintainability: Can the stylesheet be easily modified as requirements change?
- Efficiency: Does the stylesheet approach the problem using the most efficient techniques, in view of its performance requirements and the range of input it must support?
Mulberry’s technical quality review can include such factors as design efficiency, internal consistency, and correct use of XSLT constructs. We can assess the overall quality of the stylesheet suite, including formatting, modeling, and intangibles such as clarity, logic, and elegance. Based on our analysis, we describe any observed analysis or modeling irregularities, recommend immediate solutions to simple problems, and may suggest alternative approaches to major problems.