New answers tagged

1

The simplest solution is to rely on identity-based signatures. A trusted third party (TTP) defines a set of RSA keys $\mathit{mpk} = \{N,e\}$ and $\mathit{msk} = \{p,q,d\}$ where $N = pq$ for two large primes $p,q$ and $e,d$ such that $e \cdot d \equiv 1 \pmod {(p-1)(q-1)}$. Key $\mathit{mpk}$ is public and is used to check the correctness of signatures; ...


1

I believe the only way you can do this is to assume you have fixed length inputs to the hash function $f$. Otherwise, it is problematic what probability distribution you'd want to impose on the input set $\{0,1\}^{\ast}$ which is the collection of all finite input strings. In practice, hash functions do have an upper limit on the input string, but that's ...


1

So, I does anybody know how to design a module for remainder operation in >verilog that computes the remainder in a single clock cycle? Any links to >literature discussing the algorithm would suffice. A nieve implementation would be something like. parameter bitwidth; input [bitwidth-1:0] a; input [bitwidth-1:0] b; output reg [bitwidth-1:0] result; reg ...


1

Being able to validate the characters of a password independently is almost equivalent to storing the password in cleartext. If the password consists of $n$ characters in an alphabet of size $a$, then verifying hashed passwords requires $a^n$ queries. (A query is an online lookup until your password database is leaked, and a hash calculation after that.) ...


1

Validating individual letters of a password reduces complexity of guessing that password by trying all possible variants, so I would suggest avoiding such a design. PCP (probabilistic checkable proofs) is a well-known case of validating just a small portion of the "witness" (defined in that context), with focus on algorithm complexity. Regarding "1st ...


6

Many properties of boolean functions are used in stream and block cipher design, e.g., when they are used as filtering and combining functions. Some important examples are: Nonlinearity (minimal Hamming distance of the truth table of the boolean function from affine functions), must be high for resisting linear/affine approximation attacks. Correlation ...



Top 50 recent answers are included