The Skein Hash Function Family | Fast, Secure, Simple, Flexible, Efficient. And it rhymes with “rain.”

The Skein Hash Function Family | Fast, Secure, Simple, Flexible, Efficient. And it rhymes with “rain.”
Skein is a new family of cryptographic hash functions. Its design combines speed, security, simplicity, and a great deal of flexibility in a modular package that is easy to analyze.

Skein is fast. Skein-512—our primary proposal—hashes data at 6.1 clock cycles per byte on a 64-bit CPU. This means that on a 3.1 GHz x64 Core 2 Duo CPU, Skein hashes data at 500 MBytes/second per core—almost twice as fast as SHA-512 and three times faster than SHA-256. An optional hash-tree mode speeds up parallelizable implementations even more. Skein is fast for short messages, too; Skein-512 hashes short messages in about 1000 clock cycles.

Skein is secure. Our current best attack on Skein-512 is on 25 of 72 rounds, for a safety factor of 2.9. For comparison, at a similar stage in the standardization process, the AES encryption algorithm had an attack on 6 of 10 rounds, for a safety factor of only 1.7.

Fabric Engine | High-performance computing for dynamic languages

Fabric Engine | High-performance computing for dynamic languages
Fabric Engine offers a third way – we don’t think that performance should be a scarce resource, it should be a commodity that any developer can access. We provide a way for developers to provide a high-level description of concurrency that Fabric Engine dynamically compiles. We take care of the management of threading and memory and compilation so that you can concentrate on building your final product. Most importantly, we do it in a way that means we are as fast as multi-threaded C++. There is no compromise.

No Software Repositories in SuSE Enterprise on EC2

No Software Repositories in SuSE Enterprise on EC2
For anyone who knows SuSE Enterprise, you can file this one under “what a n00b!” (my SuSE experience in the past has been with openSUSE), but I recently inherited a project that required RHEL or SuSE Enterprise so they chose to deploy SuSE Enterprise on EC2 to reduce acquisition time. (Who would’ve thought a cloud provider like Amazon would be faster to acquire an install of one of these softwares that used more traditional licensing models?) Anyway, I needed to install a few extra pieces of software, but when I ran yast, its list of repositories was empty!? Turns out the fix is really easy, but I couldn’t easily find the answer within a minute or two, so I thought I’d share:

suse_register -a email=””

Yup, that was it. No license key required (at least on the EC2 build). Novell just wanted my email address.

Allen Brain Atlas: Home

Allen Brain Atlas: Home
The Allen Institute for Brain Science is an independent 501(c)(3) nonprofit medical research organization dedicated to accelerating the understanding of how the human brain works. Launched in 2003 with a generous seed contribution from philanthropist Paul G. Allen, the Institute tackles projects at the leading edge of science—far-reaching projects at the intersection of biology and technology—intended to fuel discovery for the broader scientific community worldwide.

Gerald Jay Sussman

Gerald Jay Sussman
Selected Publications of Gerald Jay Sussman

Panasonic (formerly Matsushita) Professor of Electrical Engineering (Click to see a short biography.)

Fall Term: I am teaching an unusual course in classical mechanics with Jack Wisdom. See it here.

Spring Term: I am teaching a class in symbolic programming. See it here.

Some powerful Scheme software that is used in my classes can be obtained here.
Selected Publications of Gerald Jay Sussman

Gerald Jay Sussman and Jack Wisdom, with Will Farr; Functional Differential Geometry, MIT Press, 2013.
ISBN 978-0-262-01934-7.
Alexey Radul and Gerald Jay Sussman; “Revised Report on the Propagator Model”, documentation and system, August 2010.
Alexey Radul and Gerald Jay Sussman; “The Art of the Propagator,” MIT-CSAIL-TR-2009-002; Abridged version in Proc. 2009 International Lisp Conference, March 2009.
Jacob Beal and Gerald Jay Sussman; “Engineered Robustness by Controlled Hallucination,” in AAAI 2008 Fall Symposium: “Naturally-Inspired Artificial Intelligence”, November 2008.
Daniel J. Weitzner, Harold Abelson, Tim Berners-Lee, Joan Feigenbaum, James Hendler, and Gerald Jay Sussman; “Information Accountability,” in Communications of the ACM, 51 , 6, June 2008.
Gerald Jay Sussman, “The Legacy of Computer Science,” in Computer Science, Reflections on the Field, Reflections from the Field, pp.180–183, The National Academies Press, 2004.
Ron Weiss, Thomas F. Knight, and Gerald Jay Sussman, “Genetic Process Engineering,” in Cellular Computing, Martyn Amos editor, pp.43–73, Oxford University Press, 2004.
Ron Weiss, Thomas F. Knight, and Gerald Jay Sussman, “Cellular Computation and Communication Using Engineered Genetic Regulatory Networks,” in Cellular Computing, Martyn Amos editor, pp.120–147, Oxford University Press, 2004.
Structure and Interpretation of Classical Mechanics, second edition, Gerald Jay Sussman and Jack Wisdom, MIT Press, 2014.
ISBN 978-0-262-02896-7.
“Cellular Gate Technology,” Thomas F. Knight and Gerald Jay Sussman, Proc. UMC98, First International Conference on Unconventional Models of Computation, Auckland, NZ, January 1998.
“Sparse Representations for Fast, One-shot learning”, Kenneth Yip and Gerald Jay Sussman, Proc. of National Conference on Artificial Intelligence, July 1997.
A longer version appears as MIT AI Lab Memo #1633, May 1998
“A Computational Model for the Acquisition and Use of Phonological Knowledge,” Kenneth Yip and Gerald Jay Sussman, MIT Artificial Intelligence Memo 1575, March 1996.
“Amorphous Computing,” Harold Abelson, Don Allen, Daniel Coore, Chris Hanson, George Homsy, Thomas F. Knight, Jr., Radhika Nagpal, Erik Rauch, Gerald Jay Sussman, Ron Weiss, in Communications of the ACM , 43 , 5, May 2000. Also as MIT Artificial Intelligence Memo 1665, August 1999.
“Comparison between subsonic flow simulation and physical measurements of flue pipes,” Panayotis. A. Skordos and Gerald Jay Sussman, Proceedings of ISMA 95, International Symposium on Musical Acoustics, Le Normont, France, July 1995. Also MIT Artificial Intelligence Memo 1535, April 1995.
“Spin-induced Orbital Precession and its Modulation of the Gravitational Waveforms from Merging Binaries,” T.A. Apostolatos, C. Cutler, G.J. Sussman and K.S. Thorne, Phys. Rev. D., 15 June 1994.
“Gravitational radiation from a particle in circular orbit around a black hole. II: Numerical results for the nonrotating case,” Curt Cutler, Lee Samuel Finn, Eric Poisson, and Gerald Jay Sussman, Phys. Rev. D., 47, No. 4, pp 1511–1517, Feb 1993.
“The last three minutes: measurements of coalescing compact binaries with LIGO,” C. Cutler, T.A. Apostolatos, L. Bildsten, L.S. Finn, E.E.Flanagan, D. Kennefick, D.M. Markovic, A. Ori, E. Poisson, G.J. Sussman, and K.S. Thorne, Phys. Rev. Letters, 70, pp. 2984–2988.
“Chaotic Evolution of the Solar System,” Gerald Jay Sussman and Jack Wisdom, Science, 257, 3 July 1992.
“The Supercomputer Toolkit: A general framework for special-purpose computing,” with A. Berlin, J. Katzenelson, W. McAllister, G. Rozas, G. J. Sussman, and Jack Wisdom, International Journal of High-Speed Electronics, 3, no. 3, pp. 337–361, 1992.
“Intelligence in Scientific Computing,” Hal Abelson, M. Eisenberg, M. Halfant, J. Katzenelson, E. Sacks, G.J. Sussman, J. Wisdom, K. Yip, CACM, 32, no. 5, May 1989.
“The Dynamicist’s Workbench I: Automatic preparation of numerical experiments,” Hal Abelson and Gerald Jay Sussman, in Symbolic Computation: Applications to Scientific Computing, R. Grossman (ed.), Frontiers in Applied Mathematics, vol. 5, Society for Industrial and Applied Mathematics, Philadephia, 1989.
“Lisp: a Language for Stratified Design,” Hal Abelson and Gerald Jay Sussman, Byte Magazine, February 1988, pp. 207–218.
“The Lisp Experience,” Hal Abelson, Matthew Halfant, Jacob Katzenelson and Gerald Jay Sussman, Annual Review of Computer Science, 3, 1988, pp. 167–195.
“Abstraction in Numerical Methods,” Matthew Halfant and Gerald Jay Sussman, Proc. ACM Conference on Lisp and Functional Programming, 1988.
“Advanced Computing for Science,” Piet Hut and Gerald Jay Sussman, Scientific American, 255, no. 10, October 1987.
“Numerical evidence that the motion of Pluto is chaotic,” Gerald Jay Sussman and Jack Wisdom, in Science, 241, 22 July 1988.
“The Outer Solar System for 200 Million Years,” James Applegate, M. Douglas, Y. Gursel, Gerald Jay Sussman, Jack Wisdom, Astronomical Journal, 92, pp 176-194, July 1986, reprinted in Lecture Notes in Physics #267 — Use of supercomputers in stellar dynamics, Springer Verlag, 1986.
“A Digital Orrery,” James Applegate, M. Douglas, Y. Gursel, P Hunter, C. Seitz, Gerald Jay Sussman, in IEEE Transactions on Computers, C-34, No. 9, pp. 822-831, September 1985, reprinted in Lecture Notes in Physics #267 — Use of supercomputers in stellar dynamics, Springer Verlag, 1986.
Structure and Interpretation of Computer Programs, Harold Abelson and Gerald Jay Sussman with Julie Sussman, MIT Press and McGraw-Hill, 1985, second edition 1996,
ISBN 0-262-01153-0.
(published translations in French, Japanese, Polish, Chinese, Korean, and German).
“A Model of the Radio-Continuum Filaments in the Galactic Center,” P.J. Quinn and Gerald Jay Sussman, Astrophysics Journal, 288, No.1, pp. 377-384, January 1985.
“The Best Length for a Mainspring,” Gerald Jay Sussman with Julie Sussman, Newsletter of the Massachusetts Watchmaker’s Association, pp. 8-11, June 1991.

Students who have completed PhD theses supervised by Gerald Jay Sussman.

1976: Allen Leon Brown
Qualitative Knowledge, Causal Reasoning and the Localization of Failures
1977: Drew Vincent McDermott
Flexibility and Efficiency in a Computer Program for Designing Circuits
1977: Scott Elliot Fahlman
A System for Representing and Using Real-World Knowledge
1978: Dick Waters
Automatic Analysis of the Logical Structure of Programs
1979: Johan deKleer
Causal and Teleological Reasoning in Circuit Recognition
1979: Howie Shrobe
Dependency Directed Reasoning for Complex Program Understanding
1979: Robert Carter Moore
Reasoning about Knowledge and Action
1980: Guy Lewis Steele Jr.
The Definition and Implementation of a Computer Programming Language Based on Constraints
1980: Jon Doyle
A Model for Deliberation, Action, and Introspection
1981: Charles Rich
Inspection Methods in Programming
1981: Danny Hillis
The Connection Machine
1981: Richard Brown
Coherent Behavior from Incoherent Knowledge Sources in the Automatic Synthesis of Numerical Computer Programs
1983: Thomas Francis Knight
Design of an Integrated Optical Sensor with On-Chip Preprocessing
1984: Andrew Ressler
A Circuit Grammar For Operational Amplifier Design
1984: Kenneth Forbus
Qualitative Process Theory
1987: Daniel Weise
Formal Multilevel Hierarchical Verification of Synchronous MOS Circuits
1987: David A. McAllester
ONTIC: A Knowledge Representation System for Mathematics
1988: Elisha Sacks
Automatic Qualitative Analysis of Ordinary Differential Equations Using Piecewise Linear Approximations
1989: Kenneth Man-Kam Yip
KAM: Automatic Planning and Interpretation of Numerical Experiments Using Geometrical Methods
1990: Gerald L. Roylance
Causality, constraint, & mechanism in a computer program for designing circuits
1991: John Dino Batali
Automatic Acquisition and Use of Some of the Knowledge in Physics Texts
1992: Alan Bawden
Linear Graph Reduction: Confronting the Cost of Naming
1992: Feng Zhao
Automatic Analysis and Synthesis of Controllers for Dynamical Systems Based On Phase-Space Knowledge
1992: Elizabeth Bradley
Taming Chaotic Circuits
1993: Guillermo Juan Rozas
Translucent Procedures, Abstraction without Opacity
1994: Franklyn Turbak
Slivers: Computational Modularity via Synchronized Lazy Aggregates
1994: Andrew A. Berlin
Towards Intelligent Structures: Active Control of Buckling
1995: Jon Rees
A Security Kernel Based on the Lambda-Calculus
1995: Panayotis Skordos
Modeling Flue Pipes: Subsonic Flow, Lattice Boltzmann, and Parallel Distributed Computers
1996: Thanos Siapas
Criticality and Parallelism in Combinatorial Optimization
1996: Brian LaMacchia
Internet Fish
1999: Daniel Coore
Botanical Computing: A Developmental Approach to Generating Interconnect Topologies on an Amorphous Computer
1999: Rajeev Surati
Scalable Self-Calibrating Display Technology for Seamless Large-Scale Displays
2001: Radhika Nagpal
Programmable Self-Assembly: Constructing Global Shape using Biologically-inspired Local Interactions and Origami Mathematics
2001: Ron Weiss
Cellular Computation and Communications using Engineered Genetic Regulatory Networks
2004: Erik Rauch
Diversity in Evolving Systems: Scaling and Dynamics of Genealogical Trees
2005: Attila Kondacs
Determining articulator configuration in voiced stop consonants by matching time-domain patterns in pitch periods
2006: Robert Aubrey Hearn
Games, Puzzles, and Computation
2007: Jake Beal
Learning by Learning to Communicate
2007: Piotr Mitros
Constraint-Satisfaction Modules: A Methodology for Analog Circuit Design
2009: Alexey Andreyevich Radul
Propagation Networks: A Flexible and Expressive Substrate for Computation
2012: Julie Erin Norville
Modular Design of Biological Systems
2014: Micah Zev Brodsky
Synthetic Morphogenesis: Space, time, and deformation
2017: Bonnie Kit Ying Lam
Energy Scalable Systems for 2D and 3D Low-Power Ultrasound Beamforming

Recommended Books by the Family of Gerald Jay Sussman

I CAN READ THAT! A Traveler’s Introduction to Chinese Characters.
by Julie Mazel Sussman
China Books & Periodicals
HEAVE HO! My Little Green Book of Seasickness.
by Charles Mazel
“And don’t call me a racist!” A treasury of quotes on the past, present, and future of the color line in America
Selected and arranged by Ella Mazel
AHEAD OF HER TIME: A Sampler of the Life and Thought of Mary Wollstonecraft.
Excerpts from the letters and writings of the great pioneer of the feminist movement,
Selected and arranged by Ella Mazel

Recommended Web Sites
Jim Boyk: A great pianist and teacher
Computer Science and Artificial Intelligence Laboratory (CSAIL)
Room 32G-514, The Stata Center
Massachusetts Institute of Technology
77 Massachusetts Avenue
Cambridge, MA 02139 USA
(617) 253-5874

Lighttpd – HowToSimpleSSL – lighty labs

Lighttpd – HowToSimpleSSL – lighty labs
Setting up a simple SSL configuration with Lighttpd is quite easy. Though this method should be used with care because this setup will only provide proper encryption, not authentication! The user will be presented with a query whether to accept the certificate or not!

First, go into your SSL Certificates directory and do:

cd /etc/lighttpd/certs

openssl req -new -x509 -keyout lighttpd.pem -out lighttpd.pem -days 365 -nodes

chmod 400 lighttpd.pem

The previous instuctions were saying the file should be owned by www-data (depending on the OS)

but this is a really bad idea (in case the server gets compromised etc.). As lighttpd starts

with root-privileges and drops his rights, you can safely set the owner of the certificate

to root and chmod 400 it.

Then edit /etc/lighttpd/lighttpd.conf and add:

$SERVER[“socket”] == “:443” {

ssl.engine = “enable”

ssl.pemfile = “/etc/lighttpd/certs/lighttpd.pem”


After restarting the webserver, you should be able to access your webserver via https