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Compliance Corner

Compliance corner comprises a series of issues that have arisen in the context of projects meeting technical standards. This page covers:

Migration strategy

Existing advice may be found on the Website FAQs list.

A Policy Issue

One failing that is less easy to recognise, (since it represents a failure of policy rather than a technical issue), is the incorrect use of file formats in a NOF-Digitise project __ or the failure to justify such use.

The standards require that projects should avoid using proprietary file formats, (i.e. formats owned by a particular organisation such as a company). Projects should do their utmost to adopt open standards, (e.g. (X)HTML). The guiding philosophy is that open standards make your content available to a browser, whereas proprietary formats may require some extra resource which may not always be obtainable. For example, PDF (Portable Document Format) files require a plug-in before they can be displayed in a browser. Proprietary software may be subject to disruptive change: they can become chargeable, alter their service, they can disappear altogether, and worse.

Where the content of a site is such that the adoption of a proprietary format becomes, apparently, unavoidable, projects must provide not only an explanation of the reasons for adoption, but also a documented analysis of how future effort could be directed to support open standards in accessing your content. Such an analysis is called a migration strategy and is obligatory where open standards are not adopted.

Producing a Migration Strategy

It may not always be possible to implement the strategy you have devised. However projects sometimes fail to comply not because they are using proprietary file formats but because they have not devised a full and documented migration strategy.

There is an approach to devising a migration strategy which will make it easier to establish a website's compliance despite its use of proprietary formats.

Firstly indicate the areas of your website that do not comply with NOF technical standards, for example the use of Flash in some part or a service that is externally hosted, (i.e. not part of your website under your control). Explain the importance of the non-compliant area in the overall scheme of your website, (e.g. optional extra, essential area in supporting the delivery of a key project deliverable, etc.).

Secondly explain why your approach does not meet the technical standards and what the appropriate open standard would ideally be.

Having analysed the situation, detail how you would make changes to ensure the inclusion of open standards at some time in the future, including how such work would be funded. In describing your proposed migration or transition you could demonstrate your level research by detailing the options for migration you have considered. For example, acquiring software to manage conversion from a proprietary format to an open standard as opposed to re-digitising your resources. It is therefore useful to go through the advantages and disadvantages of your chosen migration strategy.

A migration strategy proves that projects are aware of the advantages, disadvantages and consequences of their chosen policy. For examples of some migration strategy outlines and the situations they addressed, see:

PDF - A case in point

It is recognised that PDF (Portable Document Format) would appear to represent an easy solution to some projects' needs. But for all the reasons stated above, PDF could represent a rapid path to non-compliance unless it can be fully justified. It should be remembered that it is a NOF "must" requirement that content is still usable on browsers that do not have the relevant plug-ins (Section 5.1.1 PDF used alone will most likely cause accessibility problems, such as denying access to text-readers and other alternate format software, (such as those provifing different colours or larger text). PDF may also raise indexing and other technical issues.

There is also the misconception that PDF is an image format, but it was never designed as an image format, even if it can carry images. For example, images in PDF files may be subject to a degree of information loss (through compression) which may be difficult to determine. So PDF files will not display inline within webpages; a plug-in is required. Basically for people seeking to read or view your content, PDF files cannot normally be used alone in the context of the NOF-Digitise programme which is largely about online resources. Where users are expecting to read material on screen or where content contains navigation, PDF files cannot represent the sole solution.

However for projects which strongly favour the PDF format, there is no reason why material cannot be made additionally available in PDF, for example, images repurposed from, say, a TIFF format. Moreover, in the case of ensuring there are HTML files of materialin PDF, there are conversion tools, for example see:
Adobe Products at:
even if the converted HTML file may require some proof-reading and tidying up afterwards.

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Page last updated on Monday, May 09, 2005