Increased generation of reactive oxygen species (ROS) and low levels of antioxidants may cause morbidity in premature infants on supplemental oxygen. Glutathione (GSH)-dependent antioxidant systems protect against ROS, and regenerating GSH from GSH disulfide (GSSG) by the flavoenzyme GSH reductase (GR) is essential for the optimal function of this system. Previously, we have observed enhanced r...

Client puzzles have been proposed to add DOS resistance to authentication protocols. Due to the parallel design of puzzles, the technology is vulnerable to the socalled strong attacks. This paper advocates the need for time management of solved puzzle instances and introduces the “threshold puzzle” and “strong attack” concepts.

Denial of Service (DoS) attacks are a virulent type of attack on the availability of networks’ intended services and resources. Defense against DoS attacks has been built into the cryptography protocols intended for authentication and establishment of communications. However the cryptography protocols have their own vulnerability to DoS. Consequently it is desirable to provide a methodology to ...

OF THE DISSERTATION Tolerating Denial-of-Service Attacks – A System Approach by Ju Wang Doctor of Philosophy in Computer Science University of California, San Diego, 2005 Professor Andrew A. Chien, Chair Proxy network-based defense has recently emerged to address an open research challenge – protecting Internet service applications from Denial-of-Service (DoS) attacks. Such schemes use a proxy ...

in present work, we have calculated the electronic properties including density of states (dos) and electron density for gan, inn and in wurtzite phase for x=0.5. the study is based on density functional theory (dft) with full potential linearized augmented plane wave method (fp-lapw) by generalized gradient approximation (gga-pbesol) for calculating electronic properties. in this report we con...

first-principle calculations were carried out to investigate the adsorption of co over cun nanoclusters. the structural, spectroscopic and electronic properties like optimized geometries, homo (highest occupied molecular orbital) and lumo (lowest unoccupied molecular orbital) energy levels, binding energy, adsorption energy, vibrational frequency and density of states (doss) of the pure cun nan...

Denial-of-service attacks (DoS) and distributed denial-of-service attacks (DDoS) attempt to temporarily disrupt users or computer resources to cause service unavailability to legitimate users in the internetworking system. The most common type of DoS attack occurs when adversaries flood a large amount of bogus data to interfere or disrupt the service on the server. The attack can be either a si...

the interaction of a nitrosyl hydride (hno) molecule with b12n12 nanocage was explored by means of density functional calculations. it was found that hno prefers to be adsorbing on a boron atom of the cage with adsorption energy of -0.65 ev. this adsorption process significantly shifts the homo-lumo gap (eg) of the cage to lower energies, thereby reducing eg of the cage from 6.84 to 2.45 ev. ti...

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv CHAPTER 1. DENIAL OF SERVICE ATTACKS . . . . . . . . . . . . . . . 1 1.1 The Increasing Threat of DoS Attacks . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Roots of the DoS Problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.3 Classification of DoS Attacks . . . . . . . . . . . . . . . . . ....

Cryptographic puzzles (or client puzzles) are moderately difficult problems that can be solved by investing non-trivial amounts of computation and/or storage. Devising models for cryptographic puzzles has only recently started to receive attention from the cryptographic community as a first step toward rigorous models and proofs of security of applications that employ them (e.g. Denial-of-Servi...