Cryptology

Este diccionario, el más completo en el campo de la inteligencia y de la seguridad, cuenta con 1.500 términos definidos en español y con sus correspondientes traducciones al inglés, francés y portugués. Incluye también unos prácticos diccionarios inversos del inglés, francés y portugués al español, además de gráficos y tablas de uso frecuente. Un equipo multidisciplinar de una veintena de especialistas en activo ha definido cada concepto de forma sencilla y fácil de entender, cubriendo los términos especializados de estructuras de inteligencia, fuentes, análisis, diseminación y operaciones encubiertas, inteligencia económica, inteligencia competitiva, inteligencia militar, diplomacia, espionaje, terrorismo, seguridad, ética, guerra fría, recursos humanos, aspectos legales, criptografía y criptología.

With the advent of the World Wide Web and the emergence of e-commerce applications and social networks, organizations across the world generate a large amount of data daily. Data security is the utmost critical issue in ensuring safe transmission of information through the internet. Also network security issues are now becoming important as society is moving towards digital information age. As more and more users connect to the internet it attracts a lot of cyber-criminals. It comprises authorization of access to information in a network, controlled by the network administrator. The task of network security not only requires ensuring the security of end systems but of the entire network. In this paper, an attempt has been made to review the various Network Security and Cryptographic concepts. This paper discusses the state of the art for a broad range of cryptographic algorithms that are used in networking applications.

This article examines the evolution of cryptology as a business trait and a distinct state-controlled and -regulated profession in sixteenth-century Venice. It begins by briefly discussing the systematic development of cryptology in the Renaissance. Following an examination of the amateur use of codes and ciphers by members of the Venetian merchant and ruling class, and subsequently by members of all layers of Venetian society, the article moves on to discuss the professionalization of cryptology in sixteenth-century Venice. This was premised on specialist skills formation, a shared professional identity, and an emerging professional ethos. The article explores a potential link between the amateur use of cryptology, especially as it had been instigated by merchants in the form of merchant-style codes, and its professional use by the Venetian authorities. It also adds the profession of the cifrista—the professional cipher secretary—to the list of more “conventional” early modern professions.

The phenomena of secrecy have been presented in contextualizing and socially sensitive publications that rarely mention the phenomena of cryptography and code breaking. The secondary literature of cryptography focuses exclusively on enciphering methods, which are hardly contextualized as far as the wider social and intellectual environment is concerned. Furthermore, the use of early modern cryptography is rarely researched outside the political sphere of diplomacy, even though noblemen, medical doctors, scientists, university students, engineers, and everyday members of society used enciphering methods for their own purposes. This article presents a comprehensive and contextualizing history of cryptography based on the rich source material of early modern Hungary. Cryptography is contextualized in a wide range of social strata, integrated in the larger intellectual milieu of secrecy. The article surveys the most important source types of research in the field of diplomacy, inclding conspiracies, private correspondence, espionage, student handbooks, and personal diaries.

This article provides a general introduction to the subject of Cryptology, Crytography and Crytoanalysis and explains the terminology and the practical application of security techniques… In recorded History , technological innovations have revolutionized societies. The printing press is an often-cited example of the great impact one humble person's invention can have on ruling dynasties, world religions, and personal life.. Quantum encryption could rival Guttenberg's printing press in its impact. Cryptology has a fascinating History., In Warfare Cryptography is a broad, sticky, and mathematically complex, but interesting subject and an integral part of the evolution of warfare. So let's get some definitions out of the way first. Cryptology is the study of codes, both creating and solving them. Cryptography is the art of creating codes. Cryptanalysis is the art of surreptitiously revealing the contents of coded messages, breaking codes, that were not intended for you as a recipient.. Secondly, there are nomenclators and enciphers. Nomenclators are letters or numbers that represent words or phrases, like 103A means "meet me at 4PM". Ciphers are alphabetical letters or numbers that are encrypted using some sequential coding process and a key. For this essay, we will refer to both as codes. Also, enciphered, encrypted and encoded mean the same thing….Additionally, there is plain text. This is the original message that is readable and understandable, uncoded or unencrypted. Once it goes through the coding process and is encrypted, the output is readable but not understandable. There are a bunch of other terms like steganography, homophones, polyphones, digraphs, bigrams, and polygrams, but they are just variations of coding and decoding techniques. KEYWORDS Network Protocols, Mathematical Cryptology, encryption, decription 1. CRYPTOLOGY The study of cryptography and cryptanalysis. Cryptology is the mathematics, such as number theory, and the application of formulas and algorithms, that underpin cryptography and cryptanalysis. Since the cryptanalysis concepts are highly specialized and complex, we concentrate here only on some of the key mathematical concepts behind cryptography. cryptology is made up of cryptography and cryptanalysis. 1) Crytography-The art and science of making ciphers. Which concerns with the design of the cryptosystems and cryptography, is the actual securing, control, and identification of digital data. 2) Crytoanalysis-The art and science of breaking ciphers. In other words, the extraction of mm given cc, EE, DD, and possibly keke. which aims at studies relating to breaking of cryptosystems. cryptanalysis, is made up of all the attempts one might develop to undermine, circumvent, and/or break what the first part, cryptography, is attempting to accomplish. 3) Cryptosystems:-A particular suite of algorithms and protocols for encryption, decryption, and key generation. Examples: Cramer-Shoup cryptosystem, Rabin cryptosystem, Benaloh cryptosystem, RSA cryptosystem.

Today we regard cryptology, the mathematical and technical science of ciphers and codes, and philology, the humanistic study of natural or human languages and documents, as separate domains of activity. But the contiguity, even intimacy of these two domains is a historical fact with an institutional history. From the earliest documented techniques for the statistical analysis of text and experiments with mechanized literary analysis, to electromechanical and electronic code-breaking and machine translation, early literary data processing, and the computational philology of late twentieth-century humanities computing and early twenty-first-century “digital humanities,” what I call cryptophilology has flourished alongside imperial jingoism and war — and occasionally served them. In this book I argue that while computing’s humanistic applications are as every bit as historically important as its mathematical and technical origins, they are no less marked and no less constrained by the priorities of national security agencies and institutions devoted to both offensive signals intelligence and mass surveillance — and that our hope for human progress must be tempered by that, so far as even (or especially) in modern democracies, the proliferation of security institutions and the scale of their operations can be justified only by and through programmatically sustained insecurity.

Today we regard cryptology, the mathematical and technical science of ciphers and codes, and philology, the humanistic study of natural or human languages and documents, as separate domains of activity. But the contiguity, even intimacy of these two domains is a historical fact with an institutional history. From the earliest documented techniques for the statistical analysis of text and experiments with mechanized literary analysis, to electromechanical and electronic code-breaking and machine translation, early literary data processing, and the computational philology of late twentieth-century humanities computing and early twenty-first-century “digital humanities,” what I call cryptophilology has flourished alongside imperial jingoism and war — and occasionally served them. In this book I argue that while computing’s humanistic applications are as every bit as historically important as its mathematical and technical origins, they are no less marked and no less constrained by the priorities of national security agencies and institutions devoted to both offensive signals intelligence and mass surveillance — and that our hope for human progress must be tempered by that, so far as even (or especially) in modern democracies, the proliferation of security institutions and the scale of their operations can be justified only by and through programmatically sustained insecurity.

Cryptography, Steganography and Digital watermarking are widely used for Image Encryption and
Textual Data Encryption and also we have various classification of these techniques. In this paper we study of Hybrid
Cryptographic Encryption Techniques and also use of other encryption techniques to enhance their level of security
and also study of their combination of Hybrid Techniques which is included of combination of cryptographic and
Digital Watermarking Technique‟s.Hybrid approach for encryption gives more and strictly secured information, it‟s
very difficult to find out anyhow any information, none of hacker easy to detect even truly they failed to decrypt
information little bit.

In this paper we address the issue of privacy preserving data mining. Specifically, we consider a scenario in which two parties owning confidential databases wish to run a data mining algorithm on the union of their databases, without revealing any unnecessary information. Our work is motivated by the need both to protect privileged information and to enable its use for research or other purposes.

This essay proposes that securitization is underwritten by stupidity, defined as a shared social exposure to limits which condition the possibility of thinking, knowing, and communicating about threats and responses. This conceptualization of stupidity depicts security threats not as gaps in information that can be filled by a knowing subject, but encounters with difference arising from persons, communities, or nations which threaten that subject with awareness of its own stupidity. This essay subsequently reads two excesses of public discourse about ‘connecting the dots’ after 9/11, which have re-established US counterterrorism as a reliable source of knowledge. The first excess involves enhanced authorization of US decision-makers, intelligence analysts, and citizen-subjects to reliably discern threats. The second involves the figure of the terrorist threat, who is depicted as too stupid to challenge the authority of US knowledge. I conclude by considering how dubious Westernized security discourses and scholarly practices might be disrupted by placing them in relation to what Avital Ronell calls an ethic of stupidity ‘before the other’.

Sözde rastsal sayı üreteçleri ürettiği sayılar dizisi arasında ilişki kurulamayacak algoritma türleridir. Rastsal sayı üretimi fiziksel ve istatistiksel çalışmalardan kriptoloji başta olmak üzere birçok bilimsel çalışmada kullanılmaktadır. Bu çalışmada Çok Katmanlı (MLP) yapay sinir ağları kullanılarak programlama dillerinde üretilen sayıların rastsallığı arttırılmaya çalışılmıştır. Çalışmanın sonunda MATLAB programlama dilinde üretilen sıradan sözde rastsal sayılar ile yapay sinir ağı ile güçlendirilmiş sözde rastsal sayılar, rastsallık testlerine tabii tutulmuştur. Sonuç olarak yapay sinir ağlarının rastsal sayı üretiminde etkili bir yöntem olduğu tespit edilmiştir.

We describe results from an apparatus and protocol designed to implement quantum key distribution, by which two users, who share no secret information initially: (1) exchange a random quantum transmission, consisting of very faint flashes of polarized light; (2) by subsequent public discussion of the sent and received versions of this transmission estimate the extent of eavesdropping that might have taken place on it, and finally (3) if this estimate is small enough, distill from the sent and received versions a smaller body of shared random information, which is certifiably secret in the sense that any third party's expected information on it is an exponentially small fraction of one bit. Because the system depends on the uncertainty principle of quantum physics, instead of the usual mathematical assumptions such as the difficulty of factoring, it remains secure against an adversary with unlimited computing power.

The present world order is an invalid fallacy, a mere delusion to please the fancy of the self-styled elites – all those who plunged the entire Mankind into injustice, bias, inhumanity, falsehood, discord, bloodshed, abject poverty for the many and undeserved luxuries for the few, and an environmental doom at the end.

The much publicized "values" of this world simply are not values; the so-called wise scholars are not wise, and worse, they are not scholars properly speaking. They are mere fools who, from the peak of their monumental arrogance, appear as institutionalized swindlers, suitable outfits of a criminal establishment for which solidarity among members and fraudulence against all the rest matter more than faith, intuition and transcendence.

How could today´s "wise" scholars be truly wise? Their absolute lack of moral principles, their appalling indifference for our world´s real dramas and concerns, their chaotic distance from the indigenous peoples and ethno-religious groups, their detachment from the remote villages, the coastal and mountains towns, the favelas and the slums of the metropolises, their ominous isolation in libraries and research centers, their out-of-purpose elitism, and above all, their over-specialization in one sector and parallel ignorance of almost all the rest, all these fundamental characteristics of the so-called "wise" scholars of our times make of them truly and definitely unwise and useless, if not dangerous, individuals.
First published in AfroArticles, American Chronicle, and Buzzle on 8th May 2010
Republished here:
https://www.facebook.com/notes/juandryblogspotcom/stephen-hawking-the-foolish-wise-the-extraterrestrials-and-todays-criminal-elite/10150169034985655/

The goal of this paper is A) to suggest topics for a peircean semeiotics of cryptology and B) to show that, especially when compared with previous attempts, peircean semeiotics  are better suited to the study of the semiotic processes in cryptology.

The distinction between the Domain of Natural Numbers and the Domain of Line gets highlighted. This division provides the new perception to the Fermat's Conjecture, where to place it and how to prove it. The reasons why the Fermat's Conjecture remained unproven for 382 years are examined. The Fermat's Conjecture receives the proof in the Domain of Natural Numbers only. The equation a n + b n = c n with positive integers a, b, c, n is not the Fermat's Conjecture in the Domain of Line.

This paper discusses the attempt of an algorithmic approach to contribute to the decipherment of Linear A. With the assistance of software developed in Python, Linear A clusters can be compared to various dictionaries of languages respecting a certain degree of chronological and geographical compatibility, as a "brute force attack" for the reconstruction of new clusters of Linear A symbols.

In many cases the security of a cryptographic scheme based on computational Diffie–Hellman does in fact rely on the hardness of the decision Diffie–Hellman problem. In this paper we construct concrete examples of groups where the stronger hypothesis, hardness of the decision Diffie–Hellman problem, no longer holds, while the weaker hypothesis, hardness of computational Diffie–Hellman, is equivalent to the hardness of the discrete logarithm problem and still seems to be a reasonable hypothesis.

In many cases the security of a cryptographic scheme based on computational Diffie–Hellman does in fact rely on the hardness of the decision Diffie–Hellman problem. In this paper we construct concrete examples of groups where the stronger hypothesis, hardness of the decision Diffie–Hellman problem, no longer holds, while the weaker hypothesis, hardness of computational Diffie–Hellman, is equivalent to the hardness of the discrete logarithm problem and still seems to be a reasonable hypothesis.

– An increase in number of attack recorded during electronic exchange of information between the sender and the recipient in the recent years has called for a way to protect data in a robust manner. Most data transmitted over a network is sent in clear text making it easy for intruders to capture and read sensitive information. Encryption algorithms protect data from unwanted person and make sure that only the intended recipient can decipher and read the information. In this project a three tier design architecture process consisting of Blowfish algorithm for cryptography, least significant bit algorithm for steganography and handshaking a client server TCP/IP protocol, was used to develop a model for an encryption of text in image over a network system " a method for securing messages " which encrypts plain text into images before sending them to recipient. Cryptography is simply the translation of data into a secret code, and it is considered the most effective way to ensure data security. To read an encrypted file, you must have access to a secret key or password that enables you to decrypt it. Modern encryption is achieved using algorithms with a " key " to encrypt text or other data into digital nonsense and then decrypting it by restoring it to its original form. Steganography hides the existence of a secret message and in the best case nobody can see that both parties are communicating in secret. This makes steganography suitable for some tasks for which cryptography is not. The model was implemented using socket programming (Visual C#.net) to design the user interface. Every part of the systems was tested and found working.

The article presents the decipherment and translation of a little-known letter (1460) of King John II of Aragon found in the archive of the Saint Petersburg Institute of History of Russian Academy of Sciences. The author demonstrates his own approach to the decoding of the homophonic substitution cipher, which was popular in the Middle Ages. The resulting Latin text reveals the secret plan to capture Genoa proposed to the Aragonese King by Francesco Sforza, Duke of Milan. The Republic of Genoa in 1460 was under control of John II, Duke of Lorraine, who launched war a year earlier against Neapolitan King Ferdinand (Ferrante) I, nephew of John II of Aragon.

We study the design of cryptographic primitives resistant to a large class of side-channel attacks, called “memory attacks”, where an attacker can repeatedly and adaptively learn information about the secret key, subject only to the constraint that the overall amount of such information is bounded by some parameter ℓ. Although the study of such primitives was initiated only recently by Akavia et al. [2], subsequent work already produced many such “leakage-resilient” primitives [48,4,42], including signature, encryption, identification (ID) and authenticated key agreement (AKA) schemes. Unfortunately, every existing scheme, — for any of the four fundamental primitives above, — fails to satisfy at least one of the following desirable properties: Efficiency. While the construction may be generic, it should have some efficient instantiations, based on standard cryptographic assumptions, and without relying on random oracles. Strong Security. The construction should satisfy the strongest possible definition of security (even in the presence of leakage). For example, encryption schemes should be secure against chosen ciphertext attack (CCA), while signatures should be existentially unforgeable. Leakage Flexibility. It should be possible to set the scheme parameters so that the leakage bound ℓ can come arbitrarily close to the secret-key size. In this work we design the first signature, encryption, ID and AKA schemes which overcome these limitations, and satisfy all the properties above. Moreover, all our constructions are generic, in several cases elegantly simplifying and generalizing the prior constructions (which did not have any efficient instantiations). We also introduce several tools of independent interest, such as the abstraction (and constructions) of true-simulation extractable NIZK arguments, and a new deniable DH-based AKA protocol based on any CCA-secure encryption.

This paper is based on the proposed results shown in my other papers on (or hopefully soon to be on) Academia.edu. The Voynich Manuscript is considered the world's most mysterious manuscript. It uses a strange alphabet to form strange words and has strange looking images. After a hundred years, nobody has found anything comparable. Only a few of the images have near doppelgangers in other manuscripts of the time. The alphabet has no known close relatives or other examples of its use in manuscripts of the early 15 th Century or before. This paper is an attempt to weave my various Voynich Manuscript papers into one cohesive whole. It shows a possible way to read and understand the manuscript, the words, the glyph characters right from the page if the reader has memorized six groups of codes, or has a cheat sheet of the code meanings. I show the cheat sheets, the deconstruction method and sequence and the code structures and supporting material for my ideas. This paper is only trying to loosely tie them together into one larger, logical whole with branches which intertwine with each other on a solid underlying structure.

Cryptologia Publication details, including instructions for authors and subscription information: Abstract In 1967's The Broken Seal: The Story of ''Operation Magic'' and the Pearl Harbor Disaster, Ladislas Farago claimed that Herbert Yardley betrayed his country by selling decrypted Japanese diplomatic messages and the techniques used in their solution to agents of the Japanese Foreign Ministry for $7,000 [8, p. 57]. For more than four decades, the evidence Farago used to back up this claim has been interpreted differently by different researchers. We examine Farago's allegation and attempt to bring together all the evidence that references it.

We consider a security property of encryption schemes that has been surfacing increasingly often of late. We call it "key-privacy" or "anonymity". It asks that an eavesdropper in possession of a ciphertext not be able to tell which specific key, out of a set of known public keys, is the one under which the ciphertext was created-meaning the receiver is anonymous from the point of view of the adversary. We investigate the anonymity of known encryption schemes. We prove that the El Gamal scheme provides anonymity under chosen-plaintext attack assuming the Decision Diffie-Hellman problem is hard and that the Cramer-Shoup scheme provides anonymity under chosen-ciphertext attack under the same assumption. We also consider anonymity for trapdoor permutations. Known attacks indicate that the RSA trapdoor permutation is not anonymous and neither are the standard encryption schemes based on it. We provide a variant of RSA-OAEP that provides anonymity in the random oracle model assuming RSA is one-way. We also give constructions of anonymous trapdoor permutations, assuming RSA is one-way, which yield anonymous encryption schemes in the standard model.

—Debit card or ATM card frauds had been a major sector of concern due to which Reserve Bank of India (RBI) has set new guidelines since December 1, 2013. Now you will have to enter your personal identification number (PIN) every time you swipe your card at any merchant outlet. Taking the existing state of affairs into consideration, in this paper the conventional security issues of the use of ATM and debit cards are discussed along with the feasibility of other alternatives. Then, the research paper will propose a model for secure use of the debit cards and ATM cards via Chaos function and QR code (DACQ model) that bolsters both speed and security without confounding the process or making it undesirable to users.

Cryptography is taught with the basic rule that there is no such thing as an unbreakable encryption because “If someone tries enough keys he is bound to get the right one,” which gives rise to the basis of the brute force attack. Brute force attack, or exhaustive key search, is a strategy that can, in theory, be used against any encrypted data. It involves systematically checking all possible keys until the correct key is found. One of the measures of the strength of an encryption system is how long it would theoretically take an attacker to mount a successful brute-force attack against it. The so-called Landauer limit implied by the laws of physics sets a lower limit on the energy required to perform a computation of kT and the processing speed and memory requirements also set physical barriers. But with the exponential growth of computing industry supercomputers having computing capacities of 20 Peta-FLOPS and beyond have been made and a number of systems that were originally thought to be impossible to crack by brute force have nevertheless been cracked. A truly unbreakable code must not have an obtainable key. A theory for this is for the code breaker to not realize that he has broken the code even if he has the key. For example, the key and cleartext may change according to a random time variable so that even when the code has been broken the encrypted text could still represent any other meaning. This is however very impractical and has never been able to be put into effect. This paper discusses unbreakability of encryptions and proposes an encryption that can be called truly unbreakable. This paper also discusses a way of implementing an encryption that is contextually breakable and hence can only be used by random common users not criminals and terrorists because for them the code can be broken.

Linear A is an ancient writing system that was used on the island of Crete and a few surrounding Aegean areas between 1750 and 1450 BC to represent the Minoan language(s). Linear A is believed to be a syllabic script, but has yet to be deciphered; consequently, little is known about the Minoan language(s). This paper provides an analysis of recurrent clusters of symbols in order to uncover aspects of the structure of the language that Linear A transcribed. From Linear A inscriptions in readily available publications, similar, frequently recurring clusters were identified, and the comparison and analysis of these clusters yielded three aspects of variation: symbol-internal variation, inter-cluster variation, as well as variants in the wider context. With the observations from the patterns in inter-cluster variation, an approximate morphological breakdown of the clusters was derived, and plausible roots and affixes were isolated. A comparison of the clusters’ immediate environments suggests that the affixes were more likely to have been semantically motivated, while the wider contextual variation provides possible interpretations of the semantic content of the affixes themselves. This internal analysis approach, with the morphological breakdown of the clusters analysed, provides further support for the current hypothesis that the language that Linear A represented was rich in affixation.

Key words: Linear A, libation formulas, internal analysis

The Voynich manuscript is the book dated as fifteen century, written using specific and smart coding methods. This article describes the methods how it was analyzed and how coding keys were found. The last manuscript page decoding. Correlation of the last page content with John Dee notes. The proof that the Voynich manuscript and the "Book of Dunstan" - the same manuscripts. This article contains Engish (pages 1-81) and equal Russian (pages 82 - 170) versions.

Elliptic curves were being used only for mathematical studies until Miller and Koblitz introduced elliptic curves to
crypto-community in 1985 with independent works. Since then, elliptic curves became one of the most
significant tools in cryptography. Elliptic curve cryptography (ECC) started to be used for commercial purposes
after 1990's.
It provides a better level of security with the same key size than the widely used public key crypto-systems such as
RSA. Nevertheless, time complexity is not at the desired stage. Hence, there have been several studies so far that aims
to increase the time efficiency.
The curve forms that are being used for speed oriented operations came a long way in terms of gathering lower degree
formulas for scalar multiplication which is the core operation of ECC. However, one of the curve forms which is
called Huff curve could not get competitive with the other forms such as Twisted Edwards, Jacobi Quartic,
despite the studies have been made so far. This thesis focuses on increasing the efficiency of Huff form of elliptic
curve by making use of mathematical and computational primitives.

Inversion-free point addition and doubling formulas which are being used in scalar multiplication algorithms, are
proposed for the Huff curve which is defined as
y (1+a x^2) = c x (1+d y^2).
First idea is rather to embed the curve into a different projective space than the preferred for Huff curve previously.
Thus, $\mathbb{P}^1 \times \mathbb{P}^1$ embedding is used instead of $\mathbb{P}^2$ embedding. The second idea is to
make the use of isogenies in order to obtain an alternative doubling formula. Thanks to these two ideas, an improvement
is achieved.

The best algorithm for point doubling on Huff curve was computed with 6M + 5S. The proposed doubling formula in this thesis can be computed with 8M.
Also, operation count of mixed addition is decreased from 10M to 8M. Both sets of formulas are leading to an
effective cost of 2M. Furthermore, they are shown to be 4-way parallel.

We propose constructing provable collision resistant hash functions from expander graphs in which finding cycles is hard. As examples, we investigate two specific families of optimal expander graphs for provable hash function constructions: the families of Ramanujan graphs constructed by Lubotzky-Phillips-Sarnak and Pizer respectively. When the hash function is constructed from one of Pizer's Ramanujan graphs, (the set of supersingular elliptic curves over F p 2 with -isogenies, a prime different from p), then collision resistance follows from hardness of computing isogenies between supersingular elliptic curves. For the LPS graphs, the underlying hard problem is a representation problem in group theory. We estimate the cost per bit to compute these hash functions, and we implement our hash function for several members of the Pizer and LPS graph families and give actual timings.

An authenticated encryption scheme is a symmetric encryption scheme whose goal is to provide both privacy and integrity. We consider two possible notions of authenticity for such schemes, namely integrity of plaintexts and integrity of ciphertexts, and relate them (when coupled with IND-CPA) to the standard notions of privacy (IND-CCA, NM-CPA) by presenting implications and separations between all notions considered. We then analyze the security of authenticated encryption schemes designed by "generic composition," meaning making blackbox use of a given symmetric encryption scheme and a given MAC. Three composition methods are considered, namely Encrypt-and-MAC, MAC-then-encrypt, and Encrypt-then-MAC. For each of these, and for each notion of security, we indicate whether or not the resulting scheme meets the notion in question assuming the given symmetric encryption scheme is secure against chosen-plaintext attack and the given MAC is unforgeable under chosen-message attack. We provide proofs for the cases where the answer is "yes" and counter-examples for the cases where the answer is "no."

The Data Encryption Standard (DES) is the best known and most widely used cryptosystem for civilian applications. It was developed at IBM and adopted by the National Buraeu of Standards in the mid 70’s, and has successfully withstood all the attacks published so far in the open literature. In this paper we develop a new type of cryptanalytic attack which can break DES with up to eight rounds in a few minutes on a PC and can break DES with up to 15 rounds faster than an exhaustive search. The new attack can be applied to a variety of DES-like substitution/permutation cryptosystems, and demonstrates the crucial role of the (unpublished) design rules.

(this is a new version of my other paper "Some neglected arguments for the reality of Peirce’s cryptology")
(WARNING: according to at least two Peirce scholars, this is badly written; sorry about that, I do my best... I still hope this will be useful to at least a few persons...)

Peirce's interest for the science of secret communications – cryptology – has mostly past unnoticed and the aim of this paper is to describe a particular proof of his interest: Peirce's use of " deciphering " – " cryptanalysis " in the modern vocabulary – as an example of hypothesis, in two important essays on the subject, " Some Consequences of Four incapacities " and " A Theory of Probable Inference ". Section 2 discusses the role of cryptanalysis in Peirce's ideas on the art of reasoning, which introduces section 3 on the relationship between cryptanalysis and Peirce's early notion of hypothesis, in the aforementioned essays. In section 4, I do some conjectures on the possible further impact of Peirce's study of cryptanalysis on his philosophy, especially as regards the subjects of inquiry, doubt and belief. The conclusion of the paper is that not only does Peirce mentions cryptology in his works, but it is even possible that it had a pivotal importance for some of his most important theories.

Annex 1 to the paper presents a partial inventory of the references to cryptology in Peirce's works, covering the available digital versions of the Collected Papers and the Writings.

Annex 2 presents the anonymous reviews of the paper by two Peirce scholars (for the record: I agree with some of the comments and totally disagree with the tone… I get this a lot, I think reviews give scholars a chance to get their frustrations out…).

The Weil pairing, first introduced by André Weil in 1940, plays an important role in the theoretical study of the arithmetic of elliptic curves and Abelian varieties. It has also recently become extremely useful in cryptologic constructions related to those objects. This paper gives the definition of the Weil pairing, describes efficient algorithms to calculate it, gives two applications, and describes the motivation to considering it.

Hardware implementations of cryptographic algorithms are vulnerable to side-channel attacks. Side-channel attacks that are based on multiple measurements of the same operation can be countered by employing masking techniques. Many protection measures depart from an idealized hardware model that is very expensive to meet with real hardware. In particular, the presence of glitches causes many masking techniques to leak information during the computation of nonlinear functions. We discuss a recently introduced masking method which is based on secret sharing and multi-party computation methods. The approach results in implementations that are provably resistant against a wide range of attacks, while making only minimal assumptions on the hardware. We show how to use this method to derive secure implementations of some nonlinear building blocks for cryptographic algorithms. Finally, we provide a provable secure implementation of the block cipher Noekeon and verify the results by means of low-level simulations.