PDF Collaboration: WebDAV In Action - Signatures & Forms

Bernd Zipper

July 03, 2001

Editor's Note: This article is part of the PDF Collaboration: WebDAV In Action article

When Acrobat 5 was released, online digital signatures were presented as an integral part of a collaborative PDF workflow. We assumed, erroneously, that these would be handled in the same manner as online comments -- via shared folders or WebDAV. Instead, we learned that online signatures had to be implemented in a more cumbersome way, which unfortunately we were unable to test.

Due to legal requirements, a digital signature can be applied only after the whole document is saved locally and the encrypted signature embedded in the PDF file. To accomplish this online, the entire file must be downloaded, temporarily stored on a local drive, and then uploaded to the Web server via a "submit" process, generally through a CGI script. The WebDAV approach used for comments could not be used, because it would allow the signature and its PDF file to be separate -- potentially allowing substitution and negating the signature's legally binding value.

We acknowledge the necessity of this process, especially for legal contracts and other sensitive PDF files. However, we are also disappointed, since the requirement to download and upload the PDF -- especially if multiple signatures are required -- will be extremely burdensome to graphic arts users. PDFs from these users are often very large, containing full-resolution images. An online PDF "contract proof," for example, could easily be too large for practical use of digital signatures.

What About Forms?

The use of PDF forms data is also an intriguing aspect of an online workflow, although it too is separate from the WebDAV approach. Online PDFs could conceivably have a standard "cover page," including fields and check boxes, that could be integrated with a general work-flow system. Although we did not test this feature, it is still quite feasible, according to several sources at Adobe. The "submit" process for PDF forms data is well established for Web-resident documents, and will be expanded by Adobe's new $39 application, Approval, released in late August.

We expect that a number of graphic-arts developers and integrators will add forms capabilities to their online PDF offerings.

Republished with permission from The Seybold Report.