1,276 reputation
722
bio website ethanheilman.tumblr.com
location Cambridge, MA
age 32
visits member for 3 years, 4 months
seen Nov 9 at 20:46

Feb
20
comment Why programming languages don't provide simple encryption methods?
I am asking for serious failures in security that results in physical or financial damage. Such examples would make the case for simple easy to use packaged encryption in much the same way that firms which did not salt their passwords and had massive password exposures helped the security community "raise the bar" on password hashing standards.
Jan
7
awarded  Nice Question
Oct
23
comment Because the algorithm is known, it is no longer a trade secret
The NSA has several secret ciphers, called SUITE A (BATON being one of the most well known). SUITE A ciphers (not publicly revealed) are considered the most secure by the NSA (although a few type 1 ciphers are public). That is not to say the ciphers have not be subject to review, many many cryptographers work for the NSA and have attempted to break these ciphers. That being said, I'd still prefer AES256 to BATON if my life depended on it. en.wikipedia.org/wiki/BATON archives.neohapsis.com/archives/crypto/2000-q4/0028.html en.wikipedia.org/wiki/NSA_Suite_A_Cryptography
Oct
16
accepted What is the general justification for the hardness of finding preimages for cryptographic hash functions?
Oct
14
awarded  Nice Question
Oct
12
comment Could the Enigma algorithm be classified as a Feistel network?
@bob - Yep you are correct. I had always heard that the reflector was unique to enigma (since the germans patented it) and assumed the plugboard while necessary to security was a rather common feature on rotor machines at that time. Researching this further I realize I was wrong, reflectors were quite common (for example the M-325 had a reflector) but I can find no mention of plug boards prior to the enigma (although that doesn't mean there were none). quadibloc.com/crypto/ro020404.htm
Oct
4
answered Besides key and ciphertext sizes what are other advantages of elliptic curve versions of various protocols?
Oct
2
comment Could the Enigma algorithm be classified as a Feistel network?
Also FYI The trick that made enigma so powerful was not the rotators changing position (since that was common of rotor machines of that time period hence the term rotor), it was the reflector that reflected the character back through the rotors. see en.wikipedia.org/wiki/Enigma_machine#Reflector The reflector also introduced a weakness into enigma. Namely that a character could never be encoded by itself.
Sep
19
revised Could one construct a cipher that is secure for friendly parties to use but insecure for hostile parties?
added 169 characters in body
Sep
10
revised Security of simple xor and s-box cipher?
fixing minor typo
Sep
6
awarded  Necromancer
Jul
24
comment Is there a way to break this encryption?
Using the hash of the file as a public IV is extremely dangerous since it allows an attacker to try plaintexts and detect if they match. XCE would need to add randomness to plaintext to avoid this, but why not just use a random IV instead.
Jul
24
comment Is there a way to break this encryption?
@xce Under option 2 there is no way to decrypt the file since the decrypter doesn't have access to a hash of the file it can't generate the same random sequence and decrypt the file.
Jul
24
comment Designing a key expander out of ciphers
Edited post to add I just found a weakness in this.
Jul
24
revised Designing a key expander out of ciphers
found weakness
Jul
19
revised Is there difference between Algebraic Homomorphic Encryption and Fully Homomorphic Encryption Schemes?
fixing typo in title
Jul
19
suggested suggested edit on Is there difference between Algebraic Homomorphic Encryption and Fully Homomorphic Encryption Schemes?
Jul
12
awarded  Yearling
Jul
3
comment Are there any simple and yet secure encryption algorithms?
Probably the only "a priori secure" function we have is a OTP.
May
22
comment Order of cascaded ciphers
Thanks, somehow I missed that.