Re: Securing Software with License

P1ayboy wrote:

> I need advice on how to best to protect software with licenses.
>
> We are developing a windows application that people can purchase and
> download off the net, but the software needs to be protected by
> licensing.
>
> The software is being written in vb.net v1.1.
>
> If anyone knows any beeter places to post this message, please let me
> know.

I'd go for signed xml files. You can create them at your own server
and add any info you want, like the name of the customer. Signed xml is
easily read with .NET code and checked (it's build in).

Another approach is a key-code but that's less personal to the
customer and you run the risk of having your serial codes end up on
some crack site.

You can also purchase a commercial licensing library, like Xheo
licensing. These typically implement a few different ways of doing
licensing, like signed xml files or serial numbers.

Either way, you have to protect your own code from disassembling and
removal of the protection code. So obfuscate the code, sign your
assemblies, check at random places that the public token on the
assemblies is still yours and if not set a random variable to null so
the app crashes somewhere else.

That said, also read:
http://software.ericsink.com/bos/Transparency.html

about how far you should go in protecting your own software, as the
more you do to protect your software, the more you likely will annoy
your (potential) customers. :)

FB

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