Questions tagged [coding-theory]
Coding theory studies the properties of codes and their fitness for specific applications, and typically involves the removal of redundancy and the detection and/or correction of errors in transmitted data.
60 questions
1 vote
0 answers
106 views
NP-hardness of ECDLP
Qi Cheng proved that the minimum distance for elliptic linear codes (AG codes for genus 1 curves) is NP-hard (see https://arxiv.org/abs/cs/0507026). Any instance of ECDLP for an elliptic curve $E/\...
4 votes
0 answers
155 views
Is the NH hash family (from UMAC) AXU?
For any positive integer $k$, let $\boxplus_k$ be addition on $k$-bit unsigned integers and $\boxminus_k$ be subtraction on $k$-bit unsigned integers. Let $\operatorname{NH}_w((X,Y),(a,b)) = (a \...
2 votes
0 answers
120 views
Is algebraic geometry code dead?
I'm a research student and previously specialized in Algebra and number theory. Currently I'm finding a research field in Crypto/coding theory. Algebraic geometry code seems interesting to me but some ...
1 vote
1 answer
99 views
Is there a 4 by 4 NMDS matrix which is better than M= [[0,1,1,1], [1,0,1,1], [1,1,0,1], [1,1,1,0]] used in MIDORI?
Let $$M= \begin{bmatrix}0&1&1&1\\ 1&0&1&1\\ 1&1&0&1\\ 1&1&1&0\end{bmatrix}$$ which is used in the block ciphers MIDORI and MANTIS. Of course this matrix ...
1 vote
0 answers
90 views
Efficient decoding a code dual to a Goppa code?
Consider a matrix $H \in GF(2)^{a \times b}$ where $b > a$. This defines two linear codes. First, we have the code for which $H$ is the parity check matrix: $$ C = \{ \mathbf{x} \in GF(2)^b | H \...
1 vote
1 answer
95 views
Near Maximum Distance Separable Code
I want to find the minimum distance of an $[8,4]$ Near MDS code over a finite field F_4 (NMDS Code is a type of linear code). I want to know which programming language has a built-in function that ...
0 votes
1 answer
56 views
How to choose rank(A) independant columns of matrix A efficiently
Is there a better way than brute forcing (choose $k=\mathrm{rank}(A)$ first columns - test the determinant, if determinant = 0 choose new column set - there are $\binom nk$ many possibilities which is ...
3 votes
2 answers
147 views
Decrypting McEliece if security assumptions fail
1. G known - how to decrypt Referring to this question: Basic attacks on McEliece; finding S and P (nobody answered) Take a McEliece cryptosystem with public generator matrix $G′=SGP$ where $G$ is a ...
3 votes
0 answers
91 views
What are the advantages of coding based cryptosytems over LWE (Regev)?
Having recently learned of coding based cryptography, it seems that they key size for post-quantum security might be a lot larger than what is required by Regev PKE (in the former keys include several ...
6 votes
2 answers
185 views
Covering codes for digital signatures
An encryption scheme should be injective in the sense that each ciphertext should only be associated with at most one message, in order that decryption is unambiguous. An efficient signature ...
2 votes
1 answer
110 views
Too many wet positions in Wet-Paper Codes steganography with random H
I am implementing wet-paper codes (WPC) with randomly generated parity-check matrix $H$, based on this paper. As the wet DCT coefficients, I set DCT coefficients with value 0, or with values 0 and 1 (...
1 vote
0 answers
62 views
Accelerating Syndrome-Trellis Codes (STC) for GPU [closed]
From the literature, STC seems to be the current state-of-the-art for the coding part of steganography. From the description of the method, it appears to me it could be parallelized for GPU. Does ...
2 votes
1 answer
2k views
Patterson's decoding algorithm for Goppa codes
From this Wiki page: given a Goppa code $\Gamma(g, L)$ and a binary word $v=(v_0,...,v_{n-1})$, its syndrome is defined as $$s(x)=\sum_{i=0}^{n-1}\frac{v_i}{x-L_i} \mod g(x).$$ To do error correction, ...
1 vote
1 answer
191 views
Can Reed-Solomon codes work on infinite fields like $\mathbb{Q}$?
I am currently reading about RS codes. I see that they are using a Galois Fields (Finite Fields) as vector spaces. Is there any other particular reason other than the fact that they simplify binary ...
1 vote
1 answer
258 views
Use of irreducible Goppa codes in McEliece scheme
Is there a cryptographic reason for using an irreducible Goppa polynomial $g$ in the McEliece scheme? One doesn't need irreducibility to define a usable code, so I assume there is some structural ...