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We construct binary codes for fingerprinting digital documents. Our codes for n users that are -secure against c pirates have length O(c² log(n/ϵ)). This improves the codes proposed by Boneh and Shaw [1998] whose length is approximately the square of this length. The improvement carries over to works using the Boneh-Shaw code as a primitive, for example, to the dynamic traitor tracing scheme of Tassa [2005]. By proving matching lower bounds we establish that the length of our codes is best within a constant factor for reasonable error probabilities. This lower bound generalizes the bound found independently by Peikert et al. [2003] that applies to a limited class of codes. Our results also imply that randomized fingerprint codes over a binary alphabet are as powerful as over an arbitrary alphabet and the equal strength of two distinct models for fingerprinting. [ABSTRACT FROM AUTHOR]

Reversible logic is gaining significance in the context of emerging technologies such as quantum computing since reversible circuits do not lose information during computation and there is one-to-one mapping between the inputs and outputs. In this work, we present a class of new designs for reversible binary and BCD adder circuits. The proposed designs are primarily optimized for the number of ancilla inputs and the number of garbage outputs and are designed for possible best values for the quantum cost and delay. In reversible circuits, in addition to the primary inputs, some constant input bits are used to realize different logic functions which are referred to as ancilla inputs and are overheads that need to be reduced. Further, the garbage outputs which do not contribute to any useful computations but are needed to maintain reversibility are also overheads that need to be reduced in reversible designs. First, we propose two new designs for the reversible ripple carry adder: (i) one with no input carry c0 and no ancilla input bits, and (ii) one with input carry c0 and no ancilla input bits. The proposed reversible ripple carry adder designs with no ancilla input bits have less quantum cost and logic depth (delay) compared to their existing counterparts in the literature. In these designs, the quantum cost and delay are reduced by deriving designs based on the reversible Peres gate and the TR gate. Next, four new designs for the reversible BCD adder are presented based on the following two approaches: (i) the addition is performed in binary mode and correction is applied to convert to BCD when required through detection and correction, and (ii) the addition is performed in binary mode and the result is always converted using a binary to BCD converter. The proposed reversible binary and BCD adders can be applied in a wide variety of digital signal processing applications and constitute important design components of reversible computing. [ABSTRACT FROM AUTHOR]

The language JavaGI extends Java 1.5 conservatively by a generalized interface mechanism. The generalization subsumes retroactive and type-conditional interface implementations, binary methods, symmetric multiple dispatch, interfaces over families of types, and static interface methods. These features make certain coding patterns redundant, increase the expressiveness of the type system, and permit solutions to extension and integration problems with components in binary form, for which previously several unrelated extensions had been suggested. This article explains JavaGI and motivates its design. Moreover, it formalizes a core calculus for JavaGI and proves type soundness, decidability of typechecking, and determinacy of evaluation. The article also presents the implementation of a JavaGI compiler and an accompanying run-time system. The compiler, based on the Eclipse Compiler for Java, offers mostly modular static typechecking and fully modular code generation. It defers certain well-formedness checks until load time to increase flexibility and to enable full support for dynamic loading. Benchmarks show that the code generated by the compiler offers good performance. Several case studies demonstrate the practical utility of the language and its implementation. [ABSTRACT FROM AUTHOR]

A certified binary is a value together with a proof that the value satisfies a given specification. Existing compilers that generate certified code have focused on simple memory and control-flow safety rather than more advanced properties. In this article, we present a general framework for explicitly representing complex propositions and proofs in typed intermediate and assembly languages. The new framework allows us to reason about certified programs that involve effects while still maintaining decidable typechecking. We show how to integrate an entire proof system (the calculus of inductive constructions) into a compiler intermediate language and how the intermediate language can undergo complex transformations (CPS and closure conversion) while preserving proofs represented in the type system. Our work provides a foundation for the process of automatically generating certified binaries in a type-theoretic framework. [ABSTRACT FROM AUTHOR]