Hi,

I have a very basic question about viewing the NR pdf's: Why is the FileOpen plugin needed? Why are the pdf's not available wirhout the need of the FileOpen plugin? Whats the reason for making it so complicated?

Cheers
Walter

Hello, Walter.

That's a good question. Basically the reason is that NR is a business, and needs a business model where we can get paid for our work. If the book were distributed as unprotected PDFs, we'd sell about 1 copy. We know this because, for example, unprotected distribution of the Fortran version PDFs of NR 2nd Edition has basically destroyed the market for the Fortran book. Our publisher is thinking of putting it out of print.

We *hate* the plug-in, and DRM generally. We just can't figure out any other way to do business.
All suggestions welcome.

See here (http://www.nr.com/forum/showthread.php?t=922) for further discussion and links.

Cheers,
Bill P.

Hi,

thanks for your answer.
But what I do not understad is the following: If a user installs this plugin for acrobat reader, he can read and use NR, as if it would be a 'free' pdf-file. And so its free and available anyway.
So what is the purpose of the plugin? Make a protected pdf readable? If so, it does not make sense to protect the pdf in the first place, if any user (except one with special Linux configurations) can open the pdf.

Sorry for bothering you with this, but I really would like to understand the deeper meaning for this plugin.

Cheers
Walter

Hi, Walter.

The NR3 files are standard PDF files, in the sense that they completely follow the specifications set by Adobe. However, the Adobe specifications allow for the possibility that the content of the PDF file is stored in an encrypted form, and that the decryption algorithm is in a plug-in. The specific plug-in that we use, the FileOpen plug-in, verifies that your specific machine (as defined by hardware configuration and stored subscription information) is authorized on a specific subscription. If it is authorized, it decrypts the file (all within Adobe Reader). If not, not. So your statement that anyone with the plug-in can read the file is not correct -- they also have to be subscribers.

There is no such thing as perfect security, and we are certainly not attempting that -- there are at least several holes in the above security model. But, for now, it seems good enough to allow an acceptable business model and let us offer NR3 online. If the FileOpen security model ever got seriously broken, we would probably have to remove NR3 from the web, which would be too bad for legitimate users (and for us!).

Cheers,
Bill P.