We give interpretations of some known key agreement protocols in the framework of category theory and in this way we give a method of constructing of many new key agreement protocols.

Recently, a chaotic image encryption algorithm based on perceptron model was proposed. The present paper analyzes security of the algorithm and finds that the equivalent secret key can be reconstructed with only one pair of known-plaintext/ciphertext, which is supported by both mathematical proof and experiment results. In addition, some other security defects are also reported.

Stream ciphers are often used in applications where high speed and low delay are a requirement. The ISAAC keystream generator is a fast software-oriented encryption algorithm. In this papers the security of the ISAAC keystream generator is investigated. Cryptanalytic algorithm is developed for a known plaintext attack where only a small segment of plaintext is assumed to be known.

The stream cipher RC4 was designed by R.Rivest in 1987, and it is a widely deployed cipher. Many predictive states of RC4 for some special indices i were presented in the last 20 years. In this paper, we present several long term predictive states. These states increase the probability to guess part of the internal state in a known plaintext attack and present a cryptanalytic weakness of RC4. T...

The Advanced Encryption Standard (AES) is the most widely deployed block cipher. It follows the modern iterated block cipher approach, iterating a simple round function multiple times. The last round of AES slightly differs from the others, as a linear mixing operation (called MixColumns) is omitted from it. Following a statement of the designers, it is widely believed that the omission of the ...

In this paper the security of the stream cipher Vesta-2M is investigated. Cryptanalytic algorithm is developed for a known plaintext attack where only a small segment of plaintext is assumed to be known. The complexity the attack is estimated the time of searching through the square root of all possible initial states.

Major characteristics Many autistic infants are different from birth. Two common characteristics they may exhibit include arching their back away from their caregiver to avoid physical contact and failing to anticipate being picked up (i.e., becoming limp). As infants, they are often described as either passive or overly agitated babies. A passive baby refers to one who is quiet most of the tim...

The use of meta-analysis in medicine is widespread nowadays, particularly in the field of interventional cardiology. Meta-analysis is a statistical approach aiming to combine date from a large number of patients from randomized clinical studies and/or non-randomized registries so as to obtain a pooled estimate of the results and to answer specific research questions. It is important to take the...