I'd like to announce the public availability of a new polymorphic cipher that is open source and royalty-free: http://www.pmc-ciphers.com/eng/content/Backround-Info/Polymorphic-Medley-Cipher.html In the thread "polymorphic cipher"on page 3, Mr.Troutman inspired me with the words ".. cascades add complexity that is of no practical benefit to cryptographic security, yet makes the implementation harder to get right." I was digging deeper and found an interesting paper from Mr. Gazi and Mr. Maurer: P. Gazi, U. Maurer. Cascade Encryption Revisited. ASIACRYPT 2009, LNCS 5912, pp. 37–51. (2009) (ftp://ftp.inf.ethz.ch/pub/crypto/publications/GazMau09.pdf) "In a recent paper, Bellare and Rogaway showed that in the ideal cipher model, triple encryption is significantly more secure than single and double encryption, stating the security of longer cascades as an open question." Well, I thought that it might be a good idea to make a cascade of these ciphers: AES, Twofish, Serpent, Cast-256, RC6, SEED, Camellia and Anubis In order to make the task to break this cascade much harder, there exist 2^24 (approx. 16 million) different ways to cascade those ciphers. The best thing about it is the availablility of the entire source code and that it's legal to use it in any civil application. This could be interesting for programmers and for cryptanalysts. Peer review is always good and I guess that I cannot do much more to make people interested. A new code breaking challenge was launched yesterday (http://www.pmc-ciphers.com/eng/content/Backround-Info/12-2012-challenge.html). Not really much can be won, but three gold coins are better than nothing as reward for breaking a 38 bit key. The thread "polymorphic cipher" was apparently too old to add something. So I simply try to open a new thread. I'm pretty busy these days. I might thus only be able to answer a bit late.