We show that there is a very straightforward closed algebraic formula for the Rijndael block cipher. This formula is highly structured and far simpler then algebraic formulations of any other block cipher we know. The security of Rijndael depends on a new and untested hardness assumption: it is computationally infeasible to solve equations of this type. The… (More)
Abstracl. Several related algorithms are presented for computing logarithms in fields GF(p), p a prime. Heuristic arguments predict a running time of exp((1 + o(1))~/log p loglog p) for the initial precomputation phase that is needed for each p, and much shorter running times for computing individual logarithms once the precomputation is done. The running… (More)
The Diie-Hellman key exchange algorithm can be implemented using the group of points on an elliptic curve over the eld F 2 n. A software version of this using n = 155 can be optimized to achieve computation rates that are signiicantly faster than non-elliptic curve versions with a similar level of security. The fast computation of reciprocals in F 2 n is… (More)
Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94AL85000.
Software subsystems that implement cryptographic security features can be built from small modules using uniform interfaces. The methods demonstrated in this paper illustrate how configuration flexibility can be achieved and how complex services can be constructed, all using the same building block modules. These allow the configuration process to be… (More)
Security and privacy are growing concerns in the Internet community, due to the Internet's rapid growth and the desire to conduct business over it safely. This desire has led to the advent of several proposals for security standards, such as secure IP, secure HTTP, and the Secure Socket Layer. All of these standards propose using cryptographic protocols… (More)
With the increasing growth of electronic communications, it is becoming important to provide a mechanism for enforcing various security policies on network communications. This paper discusses our implementation of several previously proposed protocols that enforce the Bell LaPadula security model. We also introduce a new protocol called \Quantized Pump"… (More)