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Abstract

The popular 1024-bit key size for RSA keys is becoming the next horizon for researchers in inte factorization, as demonstrated by the innovative “TWIRL ” design recently proposed by Adi Sham Tromer. The design confirms that the traditional assumption that a 1024-bit RSA key provides co strength to an 80-bit symmetric key has been a reasonable one. Thus, if the 80-bit security level appropriate for a given application, then TWIRL itself has no immediate effect. Many details rem worked out, however, and the cost estimates are inconclusive. TWIRL provides an opportunity f key sizes in practice; RSA Laboratories ’ revised recommendations are given in Table 1 below