Dung Hoang Duong

Reducing the Key Size of the SRP Encryption Scheme

Multivariate Public Key Cryptography MPKC is one of the main candidates for secure communication in a post-quantum era. Recently, Yasuda and Sakurai proposed in [8] a new multivariate encryption scheme called SRP, which is very efficient and resists all known attacks against multivariate schemes. However, the key sizes of the scheme are quite large. In this paper we propose a new strategy to reduce the key size of the SRP scheme, which enables us to reduce the size of the public key by upi¾?to

Efficient secure matrix multiplication over LWE-based homomorphic encryption

54\,\%

Choosing Parameters for the Subfield Lattice Attack Against Overstretched NTRU

. Furthermore, we can use the additional structure in the public key polynomials to speed up the encryption process of the scheme by upi¾?to

Reducing the Key Size of the SRP Encryption Scheme - Extended version.

50\,\%

An Efficient Key Generation of ZHFE Public Key Cryptosystem

. We show by experiments that our modifications do not weaken the security of the scheme.

Fast Secure Matrix Multiplications over Ring-Based Homomorphic Encryption.

As recently been emphasized by NSA and NIST, there is an increasing need for cryptographic schemes being secure against quantum computer attacks. Especially in the area of digital signature schemes, multivariate cryptography is one of the main candidates for this. At Inscrypt 2015, Nie et al. proposed a new multivariate signature scheme called CUOVi?ź[20], whose public key consists both of quadratic and cubic polynomials. However, the scheme was broken by an attack of Hashimotoi?ź[15]. In this paper we take a closer look on the CUOV scheme and its attack and propose two new multivariate signature schemes called CSSv and SVSv, which are secure against Hashimotos attack and all other known attacks on multivariate schemes. Especially our second construction SVSv is very efficient and outperforms current multivariate signature schemes such as UOV and Rainbow in terms of key and signature size.