Cryptology ePrint Archive: Report 2015/647

Efficient ephemeral elliptic curve cryptographic keys

Andrea Miele and Arjen K. Lenstra

Abstract: We show how any pair of authenticated users can on-the-fly agree on an el- liptic curve group that is unique to their communication session, unpredictable to outside observers, and secure against known attacks. Our proposal is suitable for deployment on constrained devices such as smartphones, allowing them to efficiently generate ephemeral parameters that are unique to any single cryptographic application such as symmetric key agreement. For such applications it thus offers an alternative to long term usage of stan- dardized or otherwise pre-generated elliptic curve parameters, obtaining security against cryptographic attacks aimed at other users, and eliminating the need to trust elliptic curves generated by third parties.

Category / Keywords: public-key cryptography / ECC, Complex Multiplication, Diffie-Hellman, key exchange, sieving, ephemeral keys

Original Publication (in the same form): ISC 2015

Date: received 30 Jun 2015

Contact author: andrea miele at epfl ch

Available format(s): PDF | BibTeX Citation

Version: 20150701:010225 (All versions of this report)

Short URL: ia.cr/2015/647

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