Cryptography Weekly Newsletter

Cryptography newsletter

Top new questions this week:

Verbatim of early work on public-key cryptography?

In late 1997, the history of public-key cryptography was turned around with the announcement by the CESG (April 2000 archive) that public-key cryptography was theorized in a 1970 note [1] by James ...

public-key history  
asked by fgrieu 5 votes

Malicious DH groups

Can an attacker construct a DH group, large enough to be considered secure (say, a modulus of 2048-bits), such that the group appears safe, but the attacker is able to solve the DLP in the group ...

diffie-hellman safe-prime  
asked by xnyhps 5 votes

Real life systems that use concepts of crypto computing

Are there any working cloud/internet solutions/products that operates on encrypted data such as systems using homomorphic encryption, secure multiparty computation, electronic voting, private ...

homomorphic-encryption multiparty-computation  
asked by Kiran 2 votes
answered by mikeazo 1 vote

Is there a way to systematically calculate the public exponent $e$ in RSA?

I'm learning RSA in one of my classes and we were given a problem: $p = 5$, $q = 11$ I have done the following steps: $n = 5 \cdot 11 = 55$ $\phi = (5-1)\cdot(11-1) = 40$ I know that to ...

rsa prime-numbers  
asked by orange 2 votes
answered by fgrieu 9 votes

Gap problem for Learning With Errors

Informally, a "Gap" problem is the one that arises when solving the computational (or search) version using an oracle for the decisional version. For example, the Gap Diffie-Hellman Problem (GDH) is ...

provable-security lattice-crypto  
asked by cygnusv 2 votes

Are all binary-additive stream ciphers reciprocal?

I'm writing a thesis focused on Maurer's provably-secure stream cipher. Long story short, this cipher works by expanding a short key into a long keystream and then XORring this keystream with the ...

stream-cipher information-theory  
asked by whatyouhide 2 votes

What is the difference between order of base point and curve order in EC?

When I was read about the elliptic curve cryptography I found some definition about domain parameter of elliptic curve like the follow. But I did not understand something $p$: prime number. $a, b$: ...

asked by Mhsz 2 votes
answered by poncho 4 votes

Greatest hits from previous weeks:

What exactly is a negligible (and non-negligible) function?

The mathematical definition of neglible and non-neglible functions is fairly clear-cut, but why they are important and how they are used in cryptography?

asked by Nico Bellic 15 votes
answered by AFS 26 votes

How does one calculate the scalar multiplication on elliptic curves?

I found this example online: In the elliptic curve group defined by $$y^2 = x^3 + 9x + 17 \quad \text{over } \mathbb{F}_{23},$$ what is the discrete logarithm $k$ of $Q = (4,5)$ to the base ...

asked by Keith Lau Si Keit 3 votes
answered by PaĆ­lo Ebermann 5 votes

Can you answer these?

Can a secret message be securely transmitted within a MAC tag?

A sender wants to transmit an ultra secret code $M$ which could be either 'go', 'stop' or 'wait'. This could be any selection of code words really and adopted for any use such as transmitting short ...

encryption hash mac authenticated-encryption skein  
asked by ushadm 1 vote

Modes of encryption for hard drives?

What are the currently recommended modes of encryption for large disks? Basic requirements would seem to be that you can update an encrypted sector independently of others, which rules out most ...

encryption modes-of-operation disk-encryption  
asked by JT1 1 vote

How can I start the following crypto project?

(Cryptography: encrypting files before storage in the cloud): The project consists of a software implementation of a method to pre-process a file before storing it on a cloud storage server so that ...

encryption algorithm-design  
asked by Romy 1 vote
Subscribe to more Stack Exchange newsletters

Unsubscribe from this newsletter or change your email preferences by visiting your subscriptions page on

Questions? Comments? Let us know on our feedback site. If you no longer want to receive mail from Stack Exchange, unsubscribe from all emails.

Stack Exchange, Inc. 110 William St, 28th Floor, NY NY 10038 <3