Tag Archives: cryptography

A few Tweets

I joined Twitter at the end of December 2011 because I realized that I was using my computer less and less, and my smart phone more and more, relatively speaking — and I was using my phone to find and read content that intrigued me.  I plan to use my Twitter account almost as a note-taking service — I will tweet news articles, etc., that intrigue me and that I might want to come back to later.

My account is @aaron_sterling, and you can see it in the rightmost column of this blog.  Here are three items that are good examples of things I found interesting, but which, after today, I won’t be “elevating” to the status of a blog entry.

  1. The computer security company McAfee has produced a document titled 2012 Threat Predictions (pdf file).  I skipped over some of it, but the parts I read were fascinating.  For example, they see BitCoin as an extremely insecure currency, they believe illegal spam will diminish and be replaced by “legal spam” (equally annoying), and they think far more attackers will target hardware exploits instead of the traditional software exploits.  Worth a look.
  2. Enrique Zabala has produced a Flash animation that explains Rijndael/AES visually.  It is beautiful.
  3. Rajarshi Guha and co-authors are designing a type-ahead chemical substructure search engine.  This addresses a longstanding open problem in cheminformatics, which is: searching for chemicals in a database is slow (in worst case probably exponential because the Subgraph Isomorphism Problem is NP-complete), but can it be made faster?  At least for important special cases, this tool seems to be competitive in speed with Google’s type-ahead search engine for other content: it provides the chemist suggestions, given the prefix of the input available, before the chemist even hits the enter key.

Watermarking molecules

This post was chosen as an Editor's Selection for ResearchBlogging.orgI’ve posted twice about Anonymous hacking into Stratfor — and, more generally, their hacktivism has been making bigger and bigger waves.  CNN recently ran a fairly positive story on the support hacktivists are providing the Occupy movement.  Many of these hacktivists are quite active on Twitter and elsewhere.  However, from the perspective of both international and corporate espionage, the “quiet” hacks are the worst: someone makes off with information and the victim never knows.  As security expert Kevin Mandia told the New York Times:

The hacks that do the most damage don’t have Twitter feeds.

Another security expert, Jeremy Falkenrath, in an interview on Bloomberg News (at about 7:00 into the video), discussed, quite matter-of-factly, the hacker-for-hire market that companies in the chemical industry deploy against one another to learn trade secrets.  With this as the backdrop, I’d like to discuss one of the main open questions of cheminformatics: Is secure encryption of molecules possible?  For example, it would be nice if a company could encrypt a molecule, but then allow some third party to run in silico tests with it, having access to the molecule’s properties but not the structure itself.

Encryption of molecules

Part of the reason for the traditional closed-data policies of pharmaceutical companies is the total absence of any way to encrypt chemical structural information.  This has been recognized as an open problem for many years, the American Chemical Society held a special meeting in 2005 about it, a summary of which appeared in Nature.  While there were presenters at that meeting who felt molecular encryption was possible, and others who felt it was impossible, the practical reality as we enter 2012 is that, so far, the voices in favor of “impossible” have been correct.  Almost no new theoretical literature has been produced since 2005, and the industry appears no nearer a practical solution than it was in, say, 1975.

I recently had an idea to expand upon a proposal by Eggers et al. in 2001, to watermark in silico representations of molecules.  My idea, however, is going nowhere — just like all other attempts so far to implement chemical watermarking.  At least I can get a blog entry out of my failure though!  I hope readers of this page find my little attempt entertaining or informative.

Acknowledgement: The material in this post is based on conversations I have had with cheminformaticians Rajarshi Guha and Jörg Kurt Wegner.

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Terence Tao explains public key cryptography

Northwestern University awarded Terence Tao the 2010 Nemmers Prize in Mathematics, and, as a result, he gave a public lecture here last week.  The material was similar to the content of a presentation he gave a couple years ago that is on Youtube.  I attended the lecture at Northwestern, not so much for the material per se, but because I wanted to see how he explained mathematical concepts to a general audience.  You can’t see the effect of his words in the Youtube video, because the camera is focused on him.  I wanted to understand his interaction with the other people in the room.

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