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Digital Content Protection

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by sharpdog

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Does anyone know of a product which will prevent unauthorized capture of the contents of a web page ? I want to prevent users from saving copies of copyrighted material to their disks either through screen capture (alt-prt-scrn or 3rd party utilities) or through saving or printing the web page using their browser.

SharpDog@Mailshell.Com

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by jay eckles

This is a FAQ, actually an amalgam of a couple of FAQs.

Here's the short answer:
You cannot prevent users from saving copies of anything you put on the web.

Here's the longer answer:
There is no means by which you can prevent a user from "saving" or "capturing" any content on a web site, be it text, HTML/Javascript source, images, music or other media, or anything else. The problem is that ***by definition, when you put such material on a web site, you are making it available for download by the world***.

But let's talk practicality. Assume that you find some method that will prevent me in browser X from saving an image or printing the web page or whatever. That method is easily circumvented by using browser Y. Even easier, if the method utilizes Javascript, I just turn Javascript off in the browser.

Let's assume that you find a method that prevents me from doing these things in virtually ANY browser (you won't, but let's assume for the sake of discussion). I'll just exit my browser session, fire up telnet, and connect to your webserver on port 80. Then I'll type in the HTTP GET command by hand, and PRESTO, I'm downloading your material.

The basic lesson here is that if you put something on a public website, you're making it available to the world. If you can't allow people to have copies of your material, don't put it on your website. But you need to assess how serious this problem is to you; think about companies like Coke, FedEx, etc. that have HUGE value built upon their brand image. Yet they put their corporate logos all over their websites. You can even get a copy of the Seal of the President of the United States from whitehouse.gov, which would seem to be the ultimate "corporate logo".

Good luck.

Jay
www.jayeckles.com

by sharpdog

Hi Jay,

While you are generally correct, I have found some promising technologies that may work. The most promising one so far is one which encrypts the content using an ISAPI.DLL and then relies on a browser plug-in to decrypt the content. Theplug-in would control the licensing through a seperate encrypted communication channel to the server. Plug-ins would be available for Internet Explorer (ActiveX) and any java enabled browser using direct calls from java to a downloaded DLL (JDirect?).

While this solution will work, it takes more development time than we are willing to spend and the only company that provides something similar is charging too much -- IE. I can develop it myself for less than they charge and theirs only protects certain types of data.

by jay eckles

If you want to move away from a browser-independent solution to a browser-dependent solution, then you have a couple of options.

One, like you said, is basically a client-server approach. You encrypt the data on the server and decrypt it with a client application - the client might take the form of a Java applet running in a browser. However, if you want to prevent system-level information capture like screen shots, then you'll need a system that is written in a language less abstracted from the system. C or C++ are the obvious choices. At this point you're totally out of the browser. You'll have to write software that connects to the server via an internet connection. You could use HTTP for that connection, but a plain old socketconnection over TCP will probably be easier to implement. Now you don't have a web application; as I said, you've had to rethink what you put on the web.

There's nothing wrong whatsoever with developing and distributing a light-weight client application to view your content. Fewer people will take the time to download and install the client than would look at the website, but then again, the content is apparently sensitive.

Whether or not you can develop it yourself for less than they charge depends totally upon the requirements, what they charge, what you're capable of, and what your expenses are. It might be worth the cost of hiring a consultant to evaluate different solutions for you and do some financial analysis.

Good luck.

Jay
www.jayeckles.com

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