Joppe W. Bos, Marcelo E. Kaihara, Thorsten Kleinjung, Arjen K. Lenstra, and Peter L. Montgomery
Meeting the requirements of NIST’s new cryptographic standards means phasing out usage of 1024-bit RSA and 160-bit elliptic curve cryptography (ECC) by the end of the year 2010. This write-up comments on the vulnerability of these systems to an open community attack effort and aims to assess the risk of their continued usage beyond 2010. We conclude that for 1024-bit RSA the risk is small at least until the year 2014, and that 160-bit ECC over a prime field may safely be used for much longer – with the current state of the art in cryptanalysis we would be surprised if a public effort can make a dent in 160-bit prime field ECC by the year 2020. Our assessment is based on the latest practical data of large scale integer factorization and elliptic curve discrete logarithm computation efforts.
|Publisher||International Association for Cryptologic Research|