Martin Hellman on the Invention of Public-Key Cryptography

At the DISI conference last December, Martin Hellman gave a lecture on the invention of public-key cryptography. A video is online (it's hard to find, search for his name), along with PowerPoint slides.

(Unfortunately, the video isn't set up for streaming; in order to view the it, you'll have to download the ten files, then use a fairly recent version of WinZip to concatenate the files.)

EDITED TO ADD (3/26): Now on Google Video.

Posted on March 25, 2008 at 1:21 PM • 11 Comments


Christian VogelMarch 25, 2008 2:24 PM

It also works under unix: Download all 10 parts, then "cat hellman.* >", then unzip I used "UnZip 5.52 of 28 February 2005, by Ubuntu. Original by Info-ZIP". You will get a warning that tells you to ignore warnings, and a output file that's ok.

Josh MyerMarch 25, 2008 10:18 PM

I've taken the liberty of posting the video on google video:

I find his Q-and-A at the end disheartening. He seems to really believe that export restrictions are good because they "keep terrorists from getting inviolable secrecy." It's truly saddening, as terrorists aren't exactly opposed to smuggling things around, especially not anything as trivial to duplicate and transport as software. Perhaps the ban on hardware helps (can we still listen to the Taliban's satellite phones?), but software is a non-starter.

(As mentioned in the video summary, if the original producer would this video taken down, please contact me. I wasn't certain just how libre "Libre" meant on the page...)

Lawrence D'OliveiroMarch 25, 2008 10:42 PM

Let me second Josh Myer's comments. To pillage Bruce's words, Hellman may be a brilliant guy, but I don't think he has the "security mindset". He uncritically accepts that ongoing cryptanalysis by the NSA is an integral part of maintaining the security of the world today, and it's as though he's never come across the idea that security systems are only as strong as their weakest part, and that weakest part is not usually in the cryptographic algorithms used.

He considered himself a bit more radical in his younger days, with his "Luke Skywalker" attitude. Well, Bruce has often been just as critical in these pages, yet no-one would characterize him as "Luke Skywalker". :)

Jorge RamioMarch 26, 2008 3:54 AM

Dear Josh:
The spanish word "Libre" at CriptoRed site means "free for personal, non-commercial use".
Since CriptoRed link was included, everything it's ok.
Nevertheless, a better video quality is obtained if you download the original zip files from CriptoRed site.
Best regards
Prof. Jorge Ramio
DISI 2007 (Spain Computer Security Day) Chair

AndyMarch 26, 2008 1:07 PM

Let's say you want to get a security video cleaned up and posted to a convenient public source. You tell Bruce about it, let him post a blog entry, and other people do the assembly and posting work for you.

Almost as good as posting to Craigslist to get someone's house robbed.

Jorge RamioMarch 26, 2008 3:44 PM

Hello Andy:
I'm the chair of DISI 2007 conference and the head of CriptoRed, Cryptography and Information Security Iberoamerican Thematic Network, a Polytechnic University of Madrid public site.
Hellman's conference was zipped span mode because the size of original MWV file is too large and some countries with low Internet downloading speed could have some problem with that kind of files.
My opinion: please download from
There is no problem to assembly the files z01, z02, ..., zip and get the video.

Jorge RamioMarch 28, 2008 5:54 PM

You have the slides just up of that frame with the zip files of Martin Hellman video.
Please find the spanish text "Formato PPT, 24 páginas. Descarga directa en formato comprimido: 1.07 MB"; then see at the right side the link "Libre" that means free for download in english and clic to get the Power Point slides.
The url is:
Jorge Ramio - DISI 2007 Chair

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