A New Construction of Pseudorandom Number Generator

Random number sequences and RNGs play an important role in trusted computing environments and cryptographic applications. For example, we use random numbers in the generation of keys in TPM. In some web protocols, random numbers are applied to resist replay attacks. It is necessary to guarantee the quality of RNGs and their random sequences because deterministic factors are likely to be involved in the generation process. If a random number generator is not designed carefully, then the output number sequences may become predictable and bring high security risks. Thus, the design of random number generators that produce high-quality random number sequences has been a hot research topic in these decades. Recently, with the development of resource constrained environments, the demand of lightweight random number generators dramatically increases. People prefer to use the random number generators with extreme high efficiency in the on-the-fly applications. This will affect the security performance of the generators. In this paper, we design a random number generator which meets the current lightweight requirements in the resource-limited environments. Our design is originally based on a lightweight block cipher, and applies the property of random looking output of block cipher to the random number generators. We combine a traditional encryption mode with a novel structure for the random number generator, so that the trade-off between security and efficiency can be made perfectly. We also take a comprehensive security evaluation for our random number generator.