145 reputation
17
bio website notyet;)
location Peacedale, RI
age
visits member for 2 years, 8 months
seen 43 mins ago

Electronics Engineer, Amateur Cryptographer with interests in designing real random and psuedorandom bit generators.

"Randomness is like a box of chocolates; you never know what you are going to get"

                                                                   Forrest Gump Jr.

"You can't use mathematical means to create true randomness but you can use mathematical means to stretch a short truly random bitstream into a binary string of virtually infinite length that is indistinguishable from the uniform distribution, the distinguisher being a Universal Turing Machine". John Von Neumann Jr.

"It's trivial to make a Turing machine that fools all other Turing machines into "thinking" that they are looking at an unpredictable uniform distribution. Here is the schematic."

                                                                   Alan Turing Jr.

Aug
27
comment Testing the Fortuna random number generator?
@jochen: If you want to test the cryptographic properties you have to see if anyone can "break the generator" by using the output bits to find the secret key.
Aug
11
answered Testing the Fortuna random number generator?
Jul
12
comment Cryptographic Challenge: How to Say Something Confidentially to Snowden?
There is no reliable substitution for meeting someone in person and exchanging a private key which contains message and identity authentication bits ( I would use 128 bits for each, 256 if you are paranoid and/or smoke weed), in a OTP system or a stream cipher with a known cryptographically secure psuedorandom generator.
Jul
8
comment Are stream ciphers no longer considered by NIST?
Why the Alternating Step Generator is not used more is beyond me, there has been no public cryptanalysis(break) of this generator since it was published in 1987,26 years ago, that is long time to stand up to public scrutiny. It may be un-crackable as long as the key length is large enough, it is an amazingly simple algorithm.
Jun
20
comment Proofs of security methodologies
There are no cryptographic primitives that have proof of security unless you can show that P is not equal to NP. Just showing a reduction from some cryptographic primitive to a known hard problem in NP does not mean that the primitive is secure, you also have to prove that the problem in NP is computationally intractable. That means separating P from NP. This is well known in theoretical computer science.
Jun
15
comment Will D-Wave's quantum computers ruin classical encryption?
See Scott Aaronson's blog to see the latest info on D-Wave. Apparently D-Wave has NOT demonstrated any real quantum computing yet.
Jun
11
comment Acceptable assumptions when proving security
@WatsonLadd: Yes you can reduce the algorithm to a known hard problem but that is not proving that either is hard, to PROVE hardness ( and therefore proving security) is to prove that P is not equal to NP.
Jun
10
comment Acceptable assumptions when proving security
@WatsonLadd: There is no such thing as provable security : proving some communication system is unconditionally secure means separating the complexity classes P and NP, one of the Clay Mathematics Institute Millenium challenges.
Jun
3
comment Are there any hand ciphers not obsoleted by computer cryptanalysis?
@Luke Sheppard: Just curious , what would be your motivation for wanting a hand-generated cipher in the first place? The only scenario I can think of would be in prisons, where gangs usually communicate to their fellow gang-bangers by some kind of handwritten code.
May
17
comment Is AES really used for Top Secret stuff?
Hey Paulo, how come you never welcomed me to CST when I first signed on? I feel left out :-(
May
1
comment Should I trust CipherCloud?
Why was this closed, it has fifteen upvotes so I guess it has sparked reasonable interest. Doesn't seem to be any worse than some of the other questions posted on this site(mine included);-)
Mar
2
answered Why do we assume un-security of communication channel on every cryptography system
Feb
19
comment Are asymptotic lower bounds relevant to cryptography?
@JoeZeng: Thanks Joe, we are being kicked out now but thanks for the nice discussion :-)
Feb
19
comment Are asymptotic lower bounds relevant to cryptography?
@JoeZeng: Joe, I think you might be confused: The strength of the one time pad comes from the randomness of the KEY, not from the "function", the function is just XOR ( or XNOR if you happen to be a natural contrarian) that mixes the plaintext with the key. The key is not the function.
Feb
19
comment Are asymptotic lower bounds relevant to cryptography?
@JoeZeng: The one time pad is a one way permutation: you are using a random key and an XOR gate to perform a permutation on the plaintext. A one way permutation is a kind of one way function, read the article in Wiki for one way functions. Also read the paper by Terry Ritter " The Efficient Generation of Cryptographic Confusion Sequences". Go to section 5.1 One Way Functions and see his quote about ALL strong cryptographic systems are essentially one way functions.
Feb
19
comment Are asymptotic lower bounds relevant to cryptography?
@JoeZeng: Hi Joe, ALL "unbreakable" cryptosystems are by definition one way functions. Its an open problem in theoretical computer science as to the relationship between one way functions and the P vs NP problem.. If you can prove that the one time pad cryptosystem has nothing to do with hard on average problems in NP, step up and write a paper on it and wait for the announcement of your Turing award.
Jan
29
comment What is the most paranoid way to exchange messages?
@JeremyDicaire: Why sad? Maybe they can fall in love, give up cryptography, have a child(Eve?), live happily ever after?(not necessarily in this that order) :-)
Jan
28
comment What is the most paranoid way to exchange messages?
Taking your question at face value, obviously the most paranoid way for Alice and Bob to communicate with perfect secrecy is for Bob and Alice to meet somewhere and whisper messages into each others ear.
Dec
4
comment Bent Combining Functions
I meant no disrespect to Mr. Carlet, I was suggesting that I have no way to verify that any emails I have received are actually from the real Mr. Carlet. You have misunderstood my comment.
Dec
4
comment Bent Combining Functions
@DW: You are right , I did not define what I meant by a bent sequence , I incorrectly assumed that a bent boolean function like the AND function when used as a combining function for psuedorandom sequences will produce a bent sequence. A novice error to be sure.