Udi Ben-Porat

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The design of computer and communication systems has been based, for decades, on the fundamental assumption that the objective of all users is to improve their own performance. In recent years we have experienced a wave of DDoS attacks threatening the welfare of the Internet. These are launched by malicious users whose pure incentive is to degrade the(More)
Channel aware schedulers of modern wireless networks – such as the popular Proportional Fairness Scheduler (PFS) – improve throughput performance by exploiting channel fluctuations while maintaining fairness among the users. In order to simplify the analysis, PFS was introduced and vastly investigated in a model where frame losses do not occur, which is of(More)
In recent years we have experienced a wave of DDoS attacks threatening the welfare of the internet. These are launched by malicious users whose only incentive is to degrade the performance of other, innocent, users. The traditional systems turn out to be quite vulnerable to these attacks. The objective of this work is to take a first step to close this(More)
Channel-aware scheduling strategies – such as the CDF scheduler (CS) algorithm – provide an effective mechanism for utilizing the channel data rate for improving throughput performance in wireless data networks by exploiting channel fluctuations. A highly desired property of such a scheduling strategy is that its algorithm is stable, in the sense that no(More)
Peacock and Cuckoo hashing schemes are currently the most studied implementations for hardware network systems such as NIDS, Firewalls, etc.. In this work we evaluate their vulnerability to sophisticated complexity Denial of Service (DoS) attacks. We show that an attacker can use insertion of carefully selected keys to hit the Peacock and Cuckoo hashing(More)
Performance analysis and the design of computer and networking systems have traditionally accounted for the stochastic nature of the problem addressed and been based on stochastic type analysis, mainly expected value (“the good”). In some related disciplines, mainly computer science and algorithmic design, worst-case analysis (“the(More)
The security of Linux depends on many configuration file both at system level and application level. Most important is security of the Linux system is never static. Once you secure your Linux system it does not perpetually stay secure because operational and functional changes had done through threats or new exploits are available for packages or(More)
Performance analysis has been used for over half a century for the design and operations of computer systems and communications networks. This methodology, mostly stochastic in nature, has been based on the underlying paradigm that users are innocent and ‘‘well behaving’’. Following the flourish of the internet and the subsequent rise of malicious(More)
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