For many year, the cryptographic engineering community had worked on the problem of implementing symmetric and asymmetric ciphers as fast as possible. Typical problems were RSA accelerators or high-speed DES engines. However, the advent of ubiquitous computing has led to many pervasive devices which are extremely cost-constrained. An example are RFID tags but there are numerous other pervasive application -- ranging from automotive parts over sensor networks to consumer products such as computer gadgets -- which are extremely cost sensitive and for which cryptographic solutions have to provided with an optimized cost-performance ratio.
In this talk, I will present our research over the last few years in the area of light-weight cryptography. For asymmetric solutions, efficient hardware implementations of elliptic curve cryptosystems will be presented. We will describe a tiny ECC hardware engine which can provide elliptic curves with as little as 10,000 gates and execution times in the 100msec range for a point multiplication. In the symmetric case, we will present the smallest known DES hardware implementation. Our light-weight DES variant, DESL, further reduces the area requirements to 1800 gates. For higher security levels, both implementations can be equipped with key whitening at little extra costs and providing a security level of 112 bit.