As I said in the thread's title: does anyone knows individuals or companies willing to test the strength of an encryption algorithm by trying to break it? I mean without having access to the algorithm, just encrypted files.

This is in no way an attempt to crack some program. I'm just trying to figure out if an algorithm designed by me is of any use. And I wouldn't want the source code (and of, course, the algorithm) to be known because I could: a) make a fool out of myself if it's no good or b) if it has any practical strength someone else to take credit for it.

Thanks in advance.

There are a few people who I'm sure would try, especially if you put up a reward for someone breaking it.

As for not releasing it, I can't speak for anyone else but doubt I would ever use it without it being tested in an open environment. Imagine it did have a bug and your laptop was stolen along with the source code, whover stole it may be able to exploit it without anyone knowing.

I completely agree with David on both points: Offer a reward and they will come. Also, "security through obscurity" is not security at all. The alogrithm must be open or it will never be used.

If you do not want to look like a fool, maybe you could post it here first. Everyone here loves fools--they're really nice to me!

That would also provide a sort of a date on it and link it to you. Just a thought.

Thank both of your for the replies. The problem is that I don't have the financial resources for putting up a reward and even if I had it still would be problematic as I don't have a site to hold such "contest". In other words organizing such things would be difficult (at least for me).
As for the release of the code, it is ment to be released under the GNU/GPLicence but only if it is proven to be worthy.I don't know wether this is an insult or not. However, I've read quite a few articles on encyption algorithms made by encryption "gurus" and they all look discouraging for a starter as they say "oh, no kind of encryption is as safe as blowfish, RC2, AES, etc"...whichever algorithm they like most. Anyway, my encryption algorithm is a stream-cipher, symmetrical one and there's not such a good opinion on symmetric algorithms compared with the asymmetric ones (even if the latter relies on the first ones).

I just wanted some sort of "spare-time loosing" attempts to break such a thing only to know if I should continue working on it or should I give up. Maybe in the future I'll have the opportunity to raise contests but untill then...it looks like I'll have to do it on my own.

Sorry if you took this as an insult--it was certainly not meant as one. I simply meant that people come here either to help or to learn, and I don't think that anyone is going to consider you a fool.

Thye reward wouldn't have to be too large. Maybe you could try going to rentacoder.com and see what happens? At any rate, it sounds interesting--good luck!

Don't worry, no offence taken. I said that because I met quite a few peoples on the Internet who where replying just for their own fun, insulting peoples. I'm happy it's not your case.

Thanks for the suggestion with rent-a-coder but you see, I'm programming in my spare time, which is quite limited and in no way have the time to engage in such projects.

Anyway, I might have found a flaw in my algorithm so it will get redesigned...back to the pen and paper.
However, if anyone is willing to try (for free, unfortunately) just post a reply.