International Association for Cryptologic Research

International Association
for Cryptologic Research


Ricardo Dahab

Affiliation: University of Campinas


TinyTate: Identity-Based Encryption for Sensor Networks
In spite of several years of intense research, the area of security and cryptography in Wireless Sensor Networks (WSNs) still has a number of open problems. On the other hand, the advent of Identity-Based Encryption (IBE) has enabled a wide range of new cryptographic solutions. In this work, we argue that IBE is ideal for WSNs and vice versa. We discuss the synergy between the systems, describe how WSNs can take advantage of IBE, and present results for computation of the Tate pairing over resource constrained nodes.
An Efficient Certificateless Signature Scheme
Rafael Castro Ricardo Dahab
In this paper we present a certificateless signature (CLS) scheme secure in the Random Oracle Model. This scheme requires no pairing computations for signature generation and only two for signature verification. As far as we know, this is the only CLS scheme to require less than four pairing computations on signature verification.
Implementing Cryptographic Pairings over Barreto-Naehrig Curves
In this paper we describe an efficient implementation of the Tate and Ate pairings using Barreto-Naehrig pairing-friendly curves, on both a standard 32-bit PC and on a 32-bit smartcard. First we introduce a sub-family of such curves with a particularly simple representation. Next we consider the issues that arise in the efficient implementation of field arithmetic in $\F_{p^{12}}$, which is crucial to good performance. Various optimisations are suggested, including a novel approach to the `final exponentiation', which is faster and requires less memory than the methods previously recommended.
Efficient Certificateless Signatures Suitable for Aggregation
Rafael Castro Ricardo Dahab
This technical report describes a novel certificateless signature scheme suitable for aggregation that requires no pairing computations for signing and only 3 pairing computations for signature verification. We provide proofs for the security of single and aggregate signatures.
Multiplication and Squaring on Pairing-Friendly Fields
Pairing-friendly fields are finite fields that are suitable for the implementation of cryptographic bilinear pairings. In this paper we review multiplication and squaring methods for pairing-friendly fields $\fpk$ with $k \in \{2,3,4,6\}$. For composite $k$, we consider every possible towering construction. We compare the methods to determine which is most efficient based on the number of basic $\fp$ operations, as well as the best constructions for these finite extension fields. We also present experimental results for every method.

Program Committees

CHES 2012
CHES 2009
CHES 2007