This paper looks at the possibility of combining a block cipher and a stream cipher to get a strong hybrid cipher. It includes two specific proposals for combining AES-128 and RC4-128 to get a cipher that takes a 256-bit key and is significantly faster than AES-256, and arguably more secure. One is immune to algebraic attacks.

Abstract— These In today’s world data security is the major problem which is to be face. In order to secure data during communication, data storage and transmission we use Advance encryption standard(AES). AES is a symmetric block cipher intended to replace DES for commercial applications.it uses 128-bit block size and a key size of 128, 192, or 256 bits. The AES algorithmis use to secure data ...

The related-key model is now considered an important scenario for block cipher security and many schemes were broken in this model, even AES-192 and AES-256. Recently were introduced e cient computer-based search tools that can produce the best possible relatedkey truncated di erential paths for AES. However, one has to trust the implementation of these tools and they do not provide any meaning...

AES is the best known and most widely used block cipher. Its three versions (AES-128, AES-192, and AES-256) differ in their key sizes (128 bits, 192 bits and 256 bits) and in their number of rounds (10, 12, and 14, respectively). While for AES-128, there are no known attacks faster than exhaustive search, AES-192 and AES-256 were recently shown to be breakable by attacks which require 2 and 2 t...

In this paper we describe two different DFA attacks on the AES. The first one uses a theoretical fault model that induces a fault on only one bit of an intermediate result, hence allowing us to obtain the key by using 50 faulty ciphertexts for an AES-128. The second attack uses a more realistic fault model: we assume that we may induce a fault on a whole byte. For an AES-128, this second attack...

This paper introduces a dedicated authenticated encryption algorithm AEGIS; AEGIS allows for the protection of associated data which makes it very suitable for protecting network packets. AEGIS128L uses eight AES round functions to process a 32-byte message block (one step). AEGIS-128 uses five AES round functions to process a 16-byte message block (one step); AES-256 uses six AES round functio...

The Advanced Encryption Standard (AES) is a 128-bit block cipher with a user key of 128, 192 or 256 bits, released by NIST in 2001 as the next-generation data encryption standard for use in the USA. It was adopted as an ISO international standard in 2005. Impossible differential cryptanalysis and the boomerang attack are powerful variants of differential cryptanalysis for analysing the security...

The Square attack as a means of attacking reduced round variants of AES was described in the initial description of the Rijndael block cipher. This attack can be applied to AES, with a relatively small number of chosen plaintext-ciphertext pairs, reduced to less than six rounds in the case of AES-128 and seven rounds otherwise and several extensions to this attack have been described in the lit...

This paper provides four different architectures for encrypting and decrypting 128 bit information via the AES. The encryption algorithm includes the Key Expansion module which generates Key for all iterations on the fly, Double AEStwo-key triple AES, AESX and AES-EXE. These architectures are implemented and studied in Altera Cyclone III and STRATIX Family devices.

In this note we study security of 128-bit key 10-round AES against the boomerang attack. We show attacks on AES reduced to 5 and 6 rounds, much faster than the exhaustive key search and twice faster than the “Square” attack of the AES designers. The attacks are structural and apply to other SPN ciphers with incomplete diffusion.