This paper introduces and evaluates the performance of a novel cipher scheme, Ambiguous Multi-Symmetric Cryptography (AMSC), which conceals multiple coherent plain-texts in one cipher-text. The cipher-text can be decrypted by different keys to produce different plain-texts. Security analysis showed that AMSC is secure against cipher-text only and known plain-text attacks. AMSC has the following...

We study elliptic curve cryptosystems by first investigating the schemes defined over Zp and show that the scheme is provably secure against adaptive chosen cipher-text attack under the decisional DiffieHellman assumption. Then we derive a practical elliptic curve cryptosystem by making use of some nice elliptic curve where the decisional DiffieHellman assumption is reserved.

In this letter we report on an ultra-efficient key recovery attack under the chosen-plaintext-attack model against the stream cipher A2U2, which is the most lightweight cryptographic primitive (i.e., it costs only 284 GE in hardware implementation) proposed so far for low-cost Radio Frequency Identification (RFID) tags. Our attack can fully recover the secret key of the A2U2 cipher by only quer...

Cryptography is considered to be a disciple of science of achieving security by converting sensitive information to an un-interpretable form such that it cannot be interpreted by anyone except the transmitter and intended recipient. An innumerable set of cryptographic schemes persist in which each of it has its own affirmative and feeble characteristics. In this paper we have we have developed ...

A potential security vulnerability of embedding compression in a chaos-based cryptography is studied. Furthermore, a scheme for improving its security is proposed. This correspondence considers the use of multiple chaotic dynamics and drive chaotic trajectory by both plaintext sequence and initial values of a chaotic map. Chaotic trajectory is used for encryption that is never reused for differ...

The objective of cryptography is to make it feasible for two persons to exchange a message in such a way that other persons cannot understand. There is no end to the number of ways this can be done, but here the proposed method will be more concerned with a technique of encoding the text in such a way that the recipient can only discover the original message. The original message usually called...

The Four Stage Encryption System introduced by Acharyulu and Appaji provides secrecy even when the attacker has some samples of plain texts and their corresponding cipher texts obtained with the same key, because the cipher text generated each time, for the same plain text with the same key, is different. In other words, the system is secure against adaptive chosen-plain text attack. Another in...

One common practice when analyzing a particular cipher is the intentional weakening of the cipher to be studied. Not only does this make analysis feasible, it is also useful in that it may reveal weakness pertaining specifically to certain elements within the cipher. Such weaknesses can be used to attack a fuller version of the cipher, as well as improve the cipher’s security by fixing that par...

The GMR-2 cipher is a type of stream cipher currently being used in some Inmarsat satellite phones. It has been proven that such a cipher can be cracked using only one single-frame (15 bytes) known keystream but with a moderate executing times. In this paper, we present a new thorough security analysis of the GMR-2 cipher. We first study the inverse properties of the cipher’s components to reve...