40-bit encryption

About: 40-bit encryption is a research topic. Over the lifetime, 5434 publications have been published within this topic receiving 149016 citations.

Camellia: A 128-Bit Block Cipher Suitable for Multiple Platforms

Abstract: We present a new 128-bit block cipher called Camellia. Camellia sup- ports 128-bit block size and 128-, 192-, and 256-bit key lengths, i.e. the same interface specifications as the Advanced Encryption Standard (AES). Camellia was carefully designed to withstand all known cryptanalytic attacks and even to have a sufficiently large security leeway for use of the next 10-20 years. There are no hidden weakness inserted by the designers. It was also designed to have suitability for both software and hardware implementations and to cover all possible encryption applications that range from low-cost smart cards to high-speed network systems. Compared to the AES finalists, Camellia offers at least comparable encryption speed in software and hardware. An optimized implementation of Camellia in assembly language can en- crypt on a PentiumIII (800MHz) at the rate of m ore than 276 Mbits per second, which is much faster than the speed of an optimized DES implementation. In ad- dition, a distinguishing feature is its small hardware design. The hardware design, which includes key schedule, encryption and decryption, occupies approximately 11K gates, which is the smallest among all existing 128-bit block ciphers as far as we know. It perfectly meet current market requirements in wireless cards, for instance, where low power consumption is a mandaroty condition.

A Performance Comparison of Data Encryption Algorithms

Abstract: The principal goal guiding the design of any encryption algorithm must be security against unauthorized attacks. However, for all practical applications, performance and the cost of implementation are also important concerns. A data encryption algorithm would not be of much use if it is secure enough but slow in performance because it is a common practice to embed encryption algorithms in other applications such as e-commerce, banking, and online transaction processing applications. Embedding of encryption algorithms in other applications also precludes a hardware implementation, and is thus a major cause of degraded overall performance of the system. In this paper, the four of the popular secret key encryption algorithms, i.e., DES, 3DES, AES (Rijndael), and the Blowfish have been implemented, and their performance is compared by encrypting input files of varying contents and sizes, on different Hardware platforms. The algorithms have been implemented in a uniform language, using their standard specifications, to allow a fair comparison of execution speeds. The performance results have been summarized and a conclusion has been presented. Based on the experiments, it has been concluded that the Blowfish is the best performing algorithm among the algorithms chosen for implementation.

How to Enhance the Security of Public-Key Encryption at Minimum Cost

Abstract: This paper presents a simple and efficient conversion from a semantically secure public-key encryption scheme against passive adversaries to a non-malleable (or semantically secure) public-key encryption scheme against adaptive chosen-ciphertext attacks (active adversaries) in the random oracle model. Since our conversion requires only one random (hash) function operation, the converted scheme is almost as efficient as the original one, when the random function is replaced by a practical hash function such as SHA-1 and MD5. We also give a concrete analysis of the reduction for proving its security, and show that our security reduction is (almost) optimally efficient. Finally this paper gives some practical examples of applying this conversion to some practical and semantically secure encryption schemes such as the ElGamal, Blum-Goldwasser and Okamoto-Uchiyama schemes[4, 7, 9].

Improved efficiency for CCA-secure cryptosystems built using identity-based encryption

Abstract: Recently, Canetti, Halevi, and Katz showed a general method for constructing CCA-secure encryption schemes from identity-based encryption schemes in the standard model. We improve the efficiency of their construction, and show two specific instantiations of our resulting scheme which offer the most efficient encryption (and, in one case, key generation) of any CCA-secure encryption scheme to date.

Hierarchical identity based encryption with constant size ciphertext

Abstract: We present a Hierarchical Identity Based Encryption (HIBE) system where the ciphertext consists of just three group elements and decryption requires only two bilinear map computations, regardless of the hierarchy depth. Encryption is as efficient as in other HIBE systems. We prove that the scheme is selective-ID secure in the standard model and fully secure in the random oracle model. Our system has a number of applications: it gives very efficient forward secure public key and identity based cryptosystems (with short ciphertexts), it converts the NNL broadcast encryption system into an efficient public key broadcast system, and it provides an efficient mechanism for encrypting to the future. The system also supports limited delegation where users can be given restricted private keys that only allow delegation to bounded depth. The HIBE system can be modified to support sublinear size private keys at the cost of some ciphertext expansion.