Cryptography

"Mysteries Wrapped in Enigmas”: Trithemius, Occultism and Cryptography

by Leo Ruickbie

in Angela Catalina Ghionea (ed.), Alchemy, Medicine, Science and the Occult (Cambridge Scholars Publishing, forthcoming)

A new Challenge of hiding any encrypted secret message inside any Text/ASCII file or in MS word file : RJDA Algorithm

by Rishav Ray

Co-authored by, Jeeyan Sanyal and Debanjan Das

The present paper proposes a new method for
hiding any encrypted secret message inside a text/ASCII or more The present paper proposes a new method for
hiding any encrypted secret message inside a text/ASCII or
Microsoft word document file, by manipulating the
blank/white space characters of a cover file. Initially the
secret message is encrypted using Modified Generalized
Vernam Cipher Method (MGVCM) proposed by Nath et. al.
For hiding secret message inside any ASCII file we propose a
new method in which the bits of each character of secret
message file is inserted in place of eight randomly selected
blank space characters of the cover file. For inserting bit-0
we choose one blank space inside the cover file and to embed
bit-1 we convert the blank space to ASCII code 160 and this
is will show as blank in the screen and while printing in
paper also. To embed bit-0 and bit-1 in cover file we select
the blank spaces from cover file in random manner. The
randomly selected blank characters are read from cover file
correspond to positions of a shuffled offset matrix starting
from a certain base address in cover file. The offset matrix is
randomized using the randomization method of the
previously published MSA encryption algorithm. The
randomized embedding of message in a cover file gives an
additional layer of security over the encryption.

A Secure Variant of the Hill Cipher

by Mohsen Toorani

Proceedings of the 14th IEEE Symposium on Computers and Communications (ISCC'09), pp.313-316, July 2009

Cryptanalysis of an Elliptic Curve-based Signcryption Scheme

by Mohsen Toorani

International Journal of Network Security, Vol.10, No.1, pp.51–56, Jan. 2010

Cryptanalysis of an efficient signcryption scheme with forward secrecy based on elliptic curve

by Mohsen Toorani

Proceedings of 2008 International Conference on Computer and Electrical Engineering (ICCEE'08), pp.428-432, IEEE Computer Society, Phuket, Thailand, Dec. 2008

A Directly Public Verifiable Signcryption Scheme based on Elliptic Curves

by Mohsen Toorani

Proceedings of the 14th IEEE Symposium on Computers and Communications (ISCC'09), pp.713-716, July 2009

SMEmail - A New Protocol for the Secure E-mail in Mobile Environments

by Mohsen Toorani

Proceedings of the Australian Telecommunications Networks and Applications Conference (ATNAC'08), pp.39-44, Adelaide, Australia, Dec. 2008

A Secure Cryptosystem based on Affine Transformation

by Mohsen Toorani

Journal of Security and Communication Networks, Vol.4, No.2, PP. 207-215, Feb. 2011.

SSMS - A Secure SMS Messaging Protocol for the M-payment Systems

by Mohsen Toorani

Proceedings of the 13th IEEE Symposium on Computers and Communications (ISCC'08), pp.700-705, July 2008

THE WAR OFFICE HK POW CYPHER SYSTEM

by Hugo Rabson

A method for breaking the World War II War Office HK cypher system is described and is applied to real POW... more A method for breaking the World War II War Office HK cypher system is described and is applied to real POW correspondence.

A survey of cryptographic primitives and implementations for hardware-constrained sensor network nodes

by Rodrigo Roman

On the hardware implementation efficiency of cryptographic primitives

by Rodrigo Roman

Expected loss bounds for authentication in constrained channels

by Christos Dimitrakakis

INFOCOM 2012

We derive bounds on the expected loss for authentication protocols in channels which are constrained due to noisymore We derive bounds on the expected loss for authentication protocols in channels which are constrained due to noisy
conditions and communication costs. This is motivated by a
number of authentication protocols, where at least some part
of the authentication is performed during a phase, lasting n
rounds, with no error correction. This requires assigning an
acceptable threshold for the number of detected errors and
taking into account the cost of incorrect authentication and
of communication. This paper describes a framework enabling
an expected loss analysis for all the protocols in this family.
Computationally simple methods to obtain nearly optimal values
for the threshold, as well as for the number of rounds are
suggested and upper bounds on the expected loss, holding
uniformly, are given. These bounds are tight, as shown by a
matching lower bound. Finally, a method to adaptively select
both the number of rounds and the threshold is proposed for a
certain class of protocols

Strategi Keamanan Pesan Menggunakan Skema Subliminal Channel Ong-Schnorr-Shamir

by Muhammad Ikhsan

Tanda tangan digital (digital signature) adalah suatu mekanisme otentikasi yang memungkinkan pembuat pesan menambahkan... more Tanda tangan digital (digital signature) adalah suatu mekanisme otentikasi yang memungkinkan pembuat pesan menambahkan sebuah kode yang bertindak sebagai tanda tangannya. Skema (scheme) yang dapat digunakan untuk melakukan proses tanda tangan digital terhadap suatu pesan (message) juga ada bermacam-macam. Salah satu skemanya adalah skema Ong-Schnorr-Shamir. Skema Ong-Schnorr-Shamir merupakan skema tanda tangan digital yang berdasarkan pada persamaan linier sekuensial (sequentially linearized equations). Skema tanda tangan digital ini menggunakan polinomial modulo n. Keamanan dari skema ini didasarkan pada kesulitan untuk memecahkan persamaan polinomial. Versi dari skema yang dideskripsikan pada pembahasan kali ini adalah berdasarkan polinominal kuadratik. Skema Ong-Schnorr-Shamir Digital Signature dapat digunakan untuk menjaga keaslian data (authentication) dan keutuhan data (data integrity). Skema Ong-Schnorr-Shamir Subliminal Channel merupakan metode kriptografi yang dapat digunakan untuk menyamarkan pesan asli. Skema ini juga mendukung proses verifikasi dari skema Ong-Schnorr-Shamir Digital Signature

TSense: Trusted Sensors and Support Infrastructure

by Benedikt Kristinsson

Ardrand: The Arduino as a Hardware Random-Number Generator

by Benedikt Kristinsson

My B.Sc. thesis

Cheap micro-controllers, such as the Arduino or other controllers based on the Atmel AVR CPUs are being deployed in a... more Cheap micro-controllers, such as the Arduino or other controllers based on the Atmel AVR CPUs are being deployed in a wide variety of projects, ranging from sensors networks to robotic submarines. In this paper, we investigate the feasibility of using the Arduino as a true random number generator (TRNG). The Arduino Reference Manual recommends using it to seed a pseudo random number generator (PRNG) due to its ability to read random atmospheric noise from its analog pins. This is an enticing application since true bits of entropy are hard to come by. Unfortunately, we show by statistical methods that the atmospheric noise of an Arduino is largely predictable in a variety of settings, and is thus a weak source of entropy. We explore various methods to extract true randomness from the micro-controller and conclude that it should not be used to produce randomness from its analog pins.

Integrity Mechanism for eHealth Tele-monitoring System in Smart Home Environment

by Nikos Komninos

31st International Conference of the IEEE Engineering in
Medicine and Biology Society, September 2-6, Minnesota, USA, 2009.

During the past few years, a lot of effort has been invested in research and development of eHealth tele-monitoring... more During the past few years, a lot of effort has been invested in research and development of eHealth tele-monitoring systems that will provide many benefits for healthcare delivery from the healthcare provider to the patient's home. However, there is a plethora of security requirements in eHealth tele-monitoring systems. Data integrity of the transferred medical data is one of the most important security requirements that should be satisfied in these systems, since medical information is extremely sensitive information, and even sometimes life threatening information. In this paper, we present a data integrity mechanism for eHealth tele-monitoring system that operates in a smart home environment. Agent technology is applied to achieve data integrity with the use of cryptographic smart cards. Furthermore, the overall security infrastructure and its various components are described.

Novel methods for enabling public key schemes in future mobile systems

by Nikos Komninos

Third International Conference on 3G Mobile Communication Technologies, 2002. (Conf. Publ. No. 489)

It is essential to enable public key schemes in future mobile systems to solve current problems in authentication and... more It is essential to enable public key schemes in future mobile systems to solve current problems in authentication and key management for end-to-end security. We propose new procedures for enabling public key schemes in future mobile terminals. The proposed procedures are based on the complex public key computations that can be performed either in the SIM card or in the terminal itself Multiple cryptoprocessors are also used to decrease the processing time required to perform the complex public key computations.

Security Enhancement for A5/1 Without Losing Hardware Efficiency in Future Mobile Systems

by Nikos Komninos

IEE 3rd International Conference on 3G Mobile
Communication Technologies, IEE Conference Publication 489, London, UK, 2002, Page(s): 324-328.

A5/1 is the strong encryption algorithm which protects the air interface of the GSM cellular network. However, in the... more A5/1 is the strong encryption algorithm which protects the air interface of the GSM cellular network. However, in the Fast Software Encryption Workshop 2000, two attacks, the biased birthday attack and the random subgraph attack against A5/1 were presented. We propose new security enhancements to improve A5/1 encryption algorithm from the biased birthday attack and random subgraph attack in order to be used in future mobile communication systems. The improvements that make both attacks impractical are based on the clocking mechanism of the registers, and their key setup routine. Furthermore, we have increased the linear complexity of A5/1 to make the solution of the linear equations impractical in real time systems. Finally, both original and modified versions of A5/1 were implemented easily in a complex programmable logic device (CPLD). The modified version of A5/1 is fast, easy to implement, and most important small in size which makes it ideal for future mobile terminals.

Cryptanalysis of Advanced Encryption Standard (AES)

by Nicholas Nyakundi

This paper talks about cryptanalysis of Advanced Encryption Standard (AES). There are many attacks that have been... more This paper talks about cryptanalysis of Advanced Encryption Standard (AES). There are many attacks that have been proposed theoretically and practically to decipher ciphertexts, but it has been found that AES’s key is hard to break. Several attempts that have been made have shown that some AES rounds have been broken. Though, the attempts are on AES, they are really done on a simplified versions of AES [6][5]. Those who are trying to break the key believe that by using simplified versions to break the key, the same approach will be used to break AES key.