Abstract
In many coding and cryptography algorithms,
representations of numbers and in particular their Hamming distances
have a direct impact on their computational complexity. One such
algorithm, scalar multiplication is the central and most
timeconsuming operation in many publickey curvebased systems
such as Elliptic Curve (ECC), Hyperelliptic Curve (HECC) and
Pairingbased cryptosystems. Its algorithmic and computational
structure has been the focus of extensive research in recent years
in a growing effort to reduce its execution time and power/memory
requirements and, thus, make the corresponding system suitable for
implementation in the myriad of new applications using ubiquitous
devices such as PDAs, smartcards, cellphones, RFID tags and wireless
sensor networks.
In this talk, we present a new method for scalar multiplication that
uses a generic multibase representation to reduce the number of
required operations. Further, a multibase NAFlike algorithm that
efficiently converts numbers to such representations without
impacting memory or speed performance is developed and shown to be
sublinear in terms of the number of nonzero terms. Additional
representation reductions are discussed with the introduction of
windowbased variants that use an extended set of precomputations.
Extensive testing is carried out to show that our multibase scalar
multiplication is the fastest method to date in the setting of
ECC/HECC and exhibits a small footprint, which makes it ideal for
implementation on constrained devices.
This talk is intended to be accessible to a general audience.
Short bio: Ali Miri is a Professor with the School of Computer
Science at Ryerson University, Toronto, Canada. He is also a
Professor at the School of Information Technology and Engineering,
and the Department of Mathematics and Statistics at the University
of Ottawa, Ottawa, Canada. His research interest include applied
cryptography, digital communication, signal processing, distributed
systems, and mobile computing. He is a member of Professional
Engineers Ontario, ACM and a senior member of IEEE.
Information:
Date:  Thursday, August 5, 2010 at 14:00  Place:  Niavaran Bldg., Niavaran Square, Tehran, Iran 
