PDF Protection

There are a number of ways one can protect an e-book for download, but what about protection of distribution of that e-book.

PDF stamping is the most commonly adopted approach, albeit rather expensive for the new publisher. In this review, we look at the various PDF stamping applications available.

Standard PDF Password Protection

The standard PDF password protection does offer protection from unauthorised distribution, but does not protect the purchaser from distributing the password along with the book. For the new publisher, this is probably the only affordable option, as is at least better than no protection at all.

PDF Stamping

A PDF stamp adds a protection signature at the bottom of every page, identifying a unique user ID or email address of the licensee.

A password is entered upon opening the ebook file and validates against the stamp on each page. The advantage is that the reader does not need to be connected to the Internet to validate.

Other options are server side validation systems. In this case, the password is entered into a login page which queries the "stamp" in a server side database, meaning the ebook is restricted to reading whilst connected to the Internet.

PDF Stamp (Server License)

Cost: US$199

• Windows Server Only
• Provides greater control over the stamps than some other more expensive options.
• Does not provide encryption or password protection of the generated PDFs.
• Expensive

PDF Image Stamp Server

Cost: US$699.95

• Windows, Linux, and Mac OS X servers.
• More limited in features than Windows PDF Stamp - only able to stamp an image (not text) on each page.
• Can dynamically generate the image in PHP, to prevent screen readers from reading out the stamp.
• Does not provide encryption or password protection of the generated PDFs. This will be a deal-breaker for many.

PDF Batch Stamp Tool (Linux Server License)

Cost: US$4,500 per CPU (US$2,500 Windows Server)

• Supports virtually all server platforms.
• Extremely expensive for what it does, especially if you aren't on a Windows server.
• Can stamp, encrypt, and password-protect PDFs.
• Fast - Processing for a book-sized file takes just a few seconds.
• Used by 37signals to distribute its "Getting Real" PDF ebook

RenderX XEP Server

Cost: US$3,999.95 per CPU

• Supports PDFs generated from XSL-FO output of an XML publishing system.
• Able to individually generate, encrypt, and password-protect PDFs. Supports generation of custom PDFs to meet customers' specific requirements (e.g. purchasing individual book chapters).
• Slower processing due to complexity of process - several minutes per file
• Requires dedicated CPU. Often used in conjunction with system to notify the customer when a file is ready to be downloaded (i.e. no instant download).
  

Adobe Web Output Pak

Cost: contact Adobe ( $5k+)

• May require a Windows or Solaris web server (unless an Adobe LiveCycle product is selected, as these are Java-based).
• Contact an Adobe rep for advice.

Adobe LiveCycle Policy Server

Cost: contact Adobe ($10k+ )

• Java-based, runs on just about any server platform.
• Server side feature in Acrobat Reader 7 to manage access dynamically by communicating with your server the first time the PDF is opened.
• Access rules can be set - e.g Restricting pages for sample chapters or limiting access by time to enable time limited access to an ebook.
• Policy enforcement options are flexible, allowing customers to view documents offline (without checking with your server) if you wish to allow it.
• Requires quite  bit of server setup and may require a dedicated server.

Recommended Choice

For serious publishers and distributors of ebooks, PDF Batch Stamp Tool. is probably the best choice, even if you need to pay the premium for the Linux version (as opposed to the much less expensive Windows version)

Watch out for cheaper options - with digital publishing on the upswing, they are likely to emerge in the near future. Return to this page, and we will keep you updated.