More on PDF/A

There seems to be some serious confusion about the role of PDF/A. David Rothman of TeleRead recently wrote that “PDF/A… is not a consumer standard. It is for archivists, not the typical consumers who buy commercial e-books and other publications.” This is way wrong, although I will admit that Adobe may have contributed to the confusion by so far failing to fully promote the significance of the core of PDF becoming a full ISO standard.
First, the mobile/device implementation of PDF supplied by Adobe to partners like Sony, NTT DoCoMo, Access, Nokia, and others is effectively a small superset of PDF/A, you might say a “PDF/A+”, with the only major addition being its support for (simple) password-protected encryption. This means that anyone creating PDF/A content can be sure that content can be consumed on mobile and embedded devices as well as desktop systems.
Secondly, PDF/A sets a clear lower bar for alternative implementations of PDF viewing technology, such as the Quartz imaging model in Apple’s OS/X. This cross-platform cross-implementation portability is of value to businesses and consumers, not just archivists.
And, PDF/A highlights the underlying nature of the PDF architecture, in which by and large documents which uese new features degrade gracefully in older/subset implementations, with support for features like alternative image representations for new formats like JPEG 2000. Probably 99% of PDF files in existence today can be viewed reasonably in a PDF/A implementation. A few features, notably DRM, don’t afford backwards compatibility but so far “open DRM” has proved an oxymoron – Adobe’s seems no more or less open than any other DRM scheme out there.
Finally, there is a good reason for the subset model, beyond PDF and PDF/A. The reason is to constrain content from having programmatic application content which may be inherently unportable, and is almost certainly not going to have longevity, because it depends on particular VM versions and/or external resources like web services. Programmatic content also presents major security issues. Certainly there’s a role for highly programmatic interactive application content, but having a format that guarantees a declarative nature seems quite sensible, for consumers as well as archivists, whether that format is fixed and paginated a la PDF or reflowable a la XHTML/OEBPS.

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