http://www.eecs.ucf.edu/~dcm/Teaching/COT4810-Spring2011/Literature/SensorNetworksSurvey.pdf

Wireless sensor networks: a survey

We combine well-known techniques from the areas of error-correcting codes and cryptography to achieve a new type of cryptographic primitive that we refer to as a fuzzy commitment scheme. Like a conventional cryptographic commitment scheme, our fuzzy commitment scheme is both concealing and binding: it is infeasible for an attacker to learn the committed value, and also for the committer to decommit a value in more than one way. In a conventional scheme, a commitment must be opened using a unique witness, which acts, essentially, as a decryption key. By contrast, our scheme is fuzzy in the sense that it accepts a witness that is close to the original encrypting witness in a suitable metric, but not necessarily identical.This characteristic of our fuzzy commitment scheme makes it useful for applications such as biometric authentication systems, in which data is subject to random noise. Because the scheme is tolerant of error, it is capable of protecting biometric data just as conventional cryptographic techniques, like hash functions, are used to protect alphanumeric passwords. This addresses a major outstanding problem in the theory of biometric authentication. We prove the security characteristics of our fuzzy commitment scheme relative to the properties of an underlying cryptographic hash function.

/pdf/a-fuzzy-commitment-scheme-27akg5gt4l.pdf

A fuzzy commitment scheme

The energy usage of computer systems is becoming an important consideration, especially for battery-operated systems. Various methods for reducing energy consumption have been investigated, both at the circuit level and at the operating systems level. In this paper, we propose a simple model of job scheduling aimed at capturing some key aspects of energy minimization. In this model, each job is to be executed between its arrival time and deadline by a single processor with variable speed, under the assumption that energy usage per unit time, P, is a convex function, of the processor speed s. We give an off-line algorithm that computes, for any set of jobs, a minimum-energy schedule. We then consider some on-line algorithms and their competitive performance for the power function P(s)=s/sup p/ where p/spl ges/2. It is shown that one natural heuristic, called the Average Rate heuristic, uses at most a constant times the minimum energy required. The analysis involves bounding the largest eigenvalue in matrices of a special type.

/pdf/a-scheduling-model-for-reduced-cpu-energy-44web33myj.pdf

A scheduling model for reduced CPU energy

A sound pressure level meter adapted for use in monitoring noise levels, particularly for use by law enforcement agencies wherein the device includes means for providing a logarithmic indication of the root mean square value of ambient sound pressure levels and wherein means are provided for holding and displaying a maximum sound pressure level detected over a given period of time and for providing an alarm when a detected level exceeds a predetermined threshold level.

On the Importance of Checking Cryptographic Protocols for Faults (Extended Abstract).

We present a theoretical model for breaking various cryptographic schemes by taking advantage of random hardware faults. We show how to attack certain implementations of RSA and Rabin signatures. We also show how various authentication protocols, such as Fiat-Shamir and Schnorr, can be broken using hardware faults.

/pdf/on-the-importance-of-checking-cryptographic-protocols-for-3vphq2juta.pdf

On the importance of checking cryptographic protocols for faults

To take advantage of the full potential of ubiquitous computing, we will need systems which minimize powerconsumption. Weiser et al. and others have suggested that this may be accomplished by a CPU which dynamically changes speed and voltage, thereby saving energy by spreading run cycles into idle time. Here we continue this research, using a simulation to compare a number of policies for dynamic speed-setting. Our work clarifies a fundamental power vs. delay tradeoff, as well as the role of prediction and of smoothing in dynamic speed-setting policies. We conclude that success seemingly depends more on simple smoothing algorithms than on sophisticated prediction techniques, but defer to the replication of these results on future variable-speed systems.

Comparing algorithm for dynamic speed-setting of a low-power CPU

We review the field of result-checking, discussing simple checkers and self-correctors. We argue that such checkers could profitably be incorporated in software as an aid to efficient debugging and enhanced reliability. We consider how to modify traditional checking methodologies to make them more appropriate for use in real-time, real-number computer systems. In particular, we suggest that checkers should be allowed to use stored randomness: that is, that they should be allowed to generate, preprocess, and store random bits prior to run-time, and then to use this information repeatedly in a series of run-time checks. In a case study of checking a general real-number linear transformation (e.g., a Fourier Transform), we present a simple checker which uses stored randomness, and a self-corrector which is particularly efficient if stored randomness is employed.

Software reliability via run-time result-checking

We review the field of result-checking and suggest that it be extended to a methodology for enforcing hardware/software reliability. We thereby formulate a vision for "self-monitoring" hardware/software whose reliability is augmented through embedded suites of run-time correctness checkers. In particular, we suggest that embedded checkers and correctors may be employed to safeguard against arithmetic errors such as that which has bedeviled the Intel Pentium Microprocessor. We specify checkers and correctors suitable for monitoring the multiplication and division functionalities of an arbitrary arithmetic processor and seamlessly correcting erroneous output which may occur for any reason during the lifetime of the chip.

Reflections on the Pentium division bug

We review the field of result-checking, discussing simple checkers and self-correctors. We argue that such checkers could profitably be incorporated in software as an aid to efficient debugging and reliable functionality. We consider how to modify traditional checking methodologies to make them more appropriate for use in real-time, real-number computer systems. In particular, we suggest that checkers should be allowed to use stored randomness: i.e., that they should be allowed to generate, pre-process, and store random bits prior to run-time, and then to use this information repeatedly in a series of run-time checks. In a case study of checking a general real-number linear transformation (for example, a Fourier Transform), we present a simple checker which uses stored randomness, and a self-corrector which is particularly efficient if stored randomness is allowed. >

Program result-checking: a theory of testing meets a test of theory

The past few years have witnessed exciting discoveries in different areas of coding theory and computational number theory. The present monograph, which exhibits the author's "Habilitationsschrift," is a collection of five different topics dealing with these two important fields. We will start with a purely coding theoretic question and finish with a discussion of some problems from computational number theory. Along the way, we will gradually change our focus from coding theory to number theory. Our emphasis is almost entirely on the development of fast and practical algorithms for the problems involved. In many cases it turns out that having a view for both number theory and coding theory is a clear advantage. This is best demonstrated by Chapters 2 and 3, where we encounter most of the interrelations between coding and number theory

Hal Wasserman

Papers

Comparing algorithm for dynamic speed-setting of a low-power CPU

Software reliability via run-time result-checking

Reflections on the Pentium division bug

Program result-checking: a theory of testing meets a test of theory

Decoding algebraic-geometric codes beyond the error-correction bound