This technical report is based on a dissertation submitted January 2002 by the author for the degree of Doctor of Philosophy to the University of Cambridge, Pembroke College

We provide formal definitions and efficient secure techniques for • turning noisy information into keys usable for any cryptographic application, and, in particular, • reliably and securely authenticating biometric data. Our techniques apply not just to biometric information, but to any keying material that, unlike traditional cryptographic keys, is (1) not reproducible precisely and (2) not distributed uniformly. We propose two primitives: a fuzzy extractor reliably extracts nearly uniform randomness R from its input; the extraction is error-tolerant in the sense that R will be the same even if the input changes, as long as it remains reasonably close to the original. Thus, R can be used as a key in a cryptographic application. A secure sketch produces public information about its input w that does not reveal w, and yet allows exact recovery of w given another value that is close to w. Thus, it can be used to reliably reproduce error-prone biometric inputs without incurring the security risk inherent in storing them. We define the primitives to be both formally secure and versatile, generalizing much prior work. In addition, we provide nearly optimal constructions of both primitives for various measures of “closeness” of input data, such as Hamming distance, edit distance, and set difference.

or send email to: Technical-DOT-Reports-AT-cs-DOT-anu.edu.au A list of technical reports, including some abstracts and copies of some full reports may be found at:

retrieval system or transmitted, in any form or by any means, without the prior written permission of ARIB. 2. Notes on English Translation- ARIB Standards and Technical Reports are usually written in Japanese. This document is a translation into English of the original document for the purpose

system or transmitted, in any form or by any means, without the prior written permission of ARIB. 2. Notes on English Translation- ARIB Standards and Technical Reports are usually written in Japanese. This document is a translation into English of the original document for the purpose

retrieval system or transmitted, in any form or by any means, without the prior written permission of ARIB. 2. Notes on English Translation- ARIB Standards and Technical Reports are usually written in Japanese. This document is a translation into English of the original document for the purpose

is not practical for sensor networks, this technical report describes the RSA and ECC public-key cryptosystem implementation in the real world sensor devices. We detail the implementation of 1024-bit RSA and 160-bit ECC cryptosystems on MICAz sensor motes, the latest product of Crossbow in the MICA family. We

The National Park Service Water Resources Division is responsible for providing water resources management policy and guidelines, planning, technical assistance, training, and operational support to units of the national park system. Program areas include water rights, water resources planning

The National Park Service Water Resources Division is responsible for providing water resources management policy and guidelines, planning, technical assistance, training, and operational support to units of the national park system. Program areas include water rights, water resources planning

or send email to: