A More Secure and Efficacious TTS Signature Scheme

Abstract

-derived SFLASH family of schemes, which uses monomials in a large field for the central portion, previously usually acknowledged as fastest. We show a small flaw in TTS/2 and present an improved TTS implementation which we call TTS/4. We will examine in some detail how well TTS/4 performs, how it stands up to previously known attacks, and why it represents an advance over TTS/2. Based on this topical assessment, we consider TTS in general and TTS/4 in particular to be competitive or superior in several aspects to other schemes, partly because the theoretical roots of TTS induce many good traits. One specific area in which TTS/4 should excel is in low-cost smartcards. It seems that the genre has great potential for practical deployment and deserves further attention by the cryptological community.

Building Secure Tame-like Multivariate Public-Key Cryptosystems: The New TTS

“…This concept was adapted and extended the concept [3] to include all polynomial maps without a low degree explicit inverse for which an inverse can be found without solving anything higher than linear equations. We will call term such maps tame, and ( [3]) TTS is defined as a multivariate DSS with a tame central map. For example, with n = 28, m = 20, φ 2 : [23].…”

“…It only works if the central maps are rank-2 in some embedding field. Neither this nor any other specific attacks work against the tame-like systems that we will construct below (see [3]). …”

“…We do not want n too large because that adds to the key length and running times, and we may open ourselves to searching attacks cf. [3]. 5.…”

“…A typical multivariate PKC over the base field K has a public map comprising three portions. In the notations of [3,35], we write it as V = φ 3 • φ 2 • φ 1 : K n → K m . The maps φ 1 : w → x = M 1 w + c 1 and φ 3 : y → z = M 3 y + c 3 are affine in K n and K m respectively and usually invertible.…”

Enhanced Management of Certificate Caching and Revocation Lists in VANET

“…We are interested in two candidates: RSA and ECDSA. Table 1 taken from [13] shows performance as tested on Pentium III 500 MHz, table 2 taken from [14] shows the results on StrongARM CPU 206 MHz. Table 3 shows our results tested on Pentium 4 (3 GHz) using the Microsoft cryptographic application programming interface (CryptoAPI) and the widely used Crypto++ library [15].…”