A key component of the IP Security architecture is the Internet Key Exchange Daemon (IKE). IKE is invoked to establish keys and security related parameters between hosts in order to protected the exchanged application data with them. The IKE concept can not be used for securing group communication based on IP multicast services since it is only addressed to… (More)
An extended abstract of this paper will be presented at the Sixth Annual International Symposium on Algorithms and Computation. Abstract In 1990 Schapire gave an equivalent c haracterization of Levin's notion of functions, that are polynomial on average. This characterization gives a very smooth translation from worst case complexity t o a verage case… (More)
In this note, we show that LR(k) testing of context-free grammars with respect to random instances is many-one complete for DistNP (Distributional NP). The same result holds for testing whether a context-free grammar is LL(k), strong LL(k), SLR(k), LC(k) or strong LC(k), respectively.
Recently, Watanabe proposed a new framework for testing the correctness and average case behavior of algorithms that purport to solve a given NP search problem eeciently on average. The idea is to randomly generate certiied instances in a way that resembles the underlying distribution. We discuss this approach and show that test instances can be generated… (More)
The purpose of this paper is to give an overview of the current state of IP Security implementations for the Internet Protocol 6. The focus lies on the PC platform and the operating systems BSD, Linux, and Windows. In particular, we introduce the available implementations, describe the state of their development and the features they provide. We test the… (More)