13,566 reputation
33272
bio website paul-ebermann.tumblr.com
location Berlin, Germany
age
visits member for 3 years, 5 months
seen 9 hours ago

Don't fear to edit my posts: even if I have more reputation than you, I do make mistakes.

I'm now also a Moderator Pro Tempore (= until the first elections) at Cryptography Stack Exchange: feel free to come around and ask some cryptography questions.


My personal name is spoken as /ˈpawlo/ (IPA), in English this would be written similar to Powlo, I think (i.e. the vowels are ow and o), with an accent on the before-last syllable (which is the first in this case). It's the Esperanto form of my given name.

The photo shows my shadow, taken at night. My camera sometimes seems to forget all the other frequencies and only stores the green ones.

My current main private programming project is the game of fencing, an online abstract turn based strategy game. Implemented as a Java applet, using git as a version control system.


Some more links:


Sep
12
comment Are there cryptographic hash functions with homomorphic properties?
Yes, "homomorphic" property is the right word.
Sep
12
comment Why are we advising PKI if we know that quantum computers will break them?
You have some mixup of the terms here. Also, how do you know what the future of quantum computing is?
Sep
7
comment Change Salt when Changing Password?
If there is an internal attacker (like a rouge sysop in a bigger team – not enough to change the software, but with access to the password database – or simply stolen backups), it might be feasible to have several breaches in sequence, which might not even be noticed.
Sep
7
revised Perfectly secure shift cipher
formatting
Sep
6
comment Bit padding instead of PKCS#5 padding
Wouldn't the attack work just the same with partial bytes? If I understand right, this attack works by manipulating the previous ciphertext block which is XORed after decrypting, and you can manipulate it by individual bits just the same as by full bytes.
Aug
31
awarded  Enlightened
Aug
27
answered Security of very simple XOR with random?
Aug
27
answered Possible CPA or CCA attack when using AES-CBC mode under the following situation?
Aug
27
revised Possible CPA or CCA attack when using AES-CBC mode under the following situation?
edited tags
Aug
27
revised RSA was rejected by which journal?
edited tags
Aug
26
awarded  Nice Answer
Aug
25
revised encryption wiki excerpt
add decryption into the text.
Aug
25
awarded  public-key
Aug
24
revised Can all asymmetric key pairs be reversed?
thanks @Ricky Demer.
Aug
24
answered Counter Mode: how to choose the nonce part of the counter?
Aug
24
answered Can all asymmetric key pairs be reversed?
Aug
20
comment A patched SHA1 attempt for password verification
Collision resistance is not what you should worry about for password hashes, preimage resistance is the point.
Aug
7
awarded  Enlightened
Aug
7
awarded  Nice Answer
Jul
27
comment CSPRNG that cannot be used as random extractor
I guess for a PRNG you usually have a short input and longer output, while in a randomness extractor it is the other way around. That might be the key point of difference.