Cryptology ePrint Archive: Report 2014/385

Jacobian Coordinates on Genus 2 Curves

Huseyin Hisil and Craig Costello

Abstract: This paper presents a new projective coordinate system and new explicit algorithms which together boost the speed of arithmetic in the divisor class group of genus 2 curves. The proposed formulas generalise the use of Jacobian coordinates on elliptic curves, and their application improves the speed of performing cryptographic scalar multiplications in Jacobians of genus 2 curves over prime fields by an approximate factor of 1.25x. For example, on a single core of an Intel Core i7-3770M (Ivy Bridge), we show that replacing the previous best formulas with our new set improves the cost of generic scalar multiplications from 243,000 to 195,000 cycles, and drops the cost of specialised GLV-style scalar multiplications from 166,000 to 129,000 cycles.

Category / Keywords: public-key cryptography / Genus 2, hyperelliptic curves, explicit formulas, Jacobian coordinates, scalar multiplication.

Date: received 28 May 2014, last revised 31 May 2014

Contact author: huseyin hisil at yasar edu tr

Available format(s): PDF | BibTeX Citation

Version: 20140531:210022 (All versions of this report)

Short URL: ia.cr/2014/385

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