Gendu Zhang

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IP traceback is one of the most effective techniques to defeat the denial-of-service attacks and distributed denial-of-service attacks. And based on previous research, available probabilistic packet marking (PPM) schemes have more advantages than other IP traceback techniques. But the traditional schemes have too low marking packets utilization. In this(More)
Distributed denial-of-service attacks have become the major threat to Internet today. IP traceback is one of the most effective techniques to defeat these attacks by identifying attack sources even in the presence of IP spoofing. Because of low marking packet utilization, the convergence time of traditional probabilistic packet marking (PPM) schemes is(More)
In order to assess the security of network information system, many graph-based approaches have been proposed. Attack Graph is the most influential one. But attack graphs grow exponentially with the size of the network. In this paper, we propose an improved access graph based model to analyze network security. As a complement to the attack graph approach,(More)
The researches on the cryptographic protocols, especially on the formal analysis methods, have been paid much attention to in the last two decades. However, the formal methods already presented can not perfectly prove a protocol really secure. In this paper, we unfold the properties that cryptographic protocols should possess and then prove, with respect to(More)
We show that the protocol proposed by Xu, Zhang and Zhu in 3] is not secure under the assumptions and deenitions made by the authors. In 3] the authors presented some explicit assumptions and the properties that a secure cryptographic protocol should hold. In this framework they presented a protocol which they claimed is totally secure with respect to the(More)