Power exponentiation is an important operation in modern cryptography. This operation can be efficiently calculated using the concept of the addition chain. In this paper, two new systematic methods, a Run-length method and a Hybrid method, are proposed to generate a short addition chain. The performance of these two methods are theoretically analyzed and it is shown that the Hybrid method is m...

In this paper, we propose a variant of Chord system that is resilient to routing attacks. By routing attacks, we mean the attacks which detour the looking up messages, aiming to disrupt the performance of data look-up systems by increasing the path length of queries. Chord routes messages uni-directionally and has no bi-directional edges. While its performance in the absence of routing attacks ...

A graph theoretic approach is proposed to formulate communication graphs that enable ultrafast information distribution. In our earlier work, we reported that Borel Cayley graph (BCG) is potentially a good candidate as a logical topology for fast information distribution. However, the practical applications of BCG have been challenging because of its inflexible sizes. In this paper, we propose ...

In this paper an analytical framework is proposed for the evaluation of the tradeo s between location privacy and energy e ciency in wireless sensor networks. We assume that random routing is utilized to improve privacy. However, this involves an increase in the average path length and thus an increase in energy consumption. The privacy loss is measured using information theory concepts; indeed...

This paper clarifies the relation between synchronization and graph topology. Applying the Connection Graph Stability method developed by Belykh et al. [2004a] to the study of synchronization in networks of coupled oscillators, we show which graph properties matter for synchronization. In particular, while we explicitly link the stability of synchronization with the average path length for a wi...

There are few studies that look closely at how the topology of the Internet evolves over time; most focus on snapshots taken at a particular point in time. In this paper, we investigate the evolution of the topology of the Autonomous Systems graph of the Internet, examining how eight commonlyused topological measures change from January 2002 to January 2010. We find that the distributions of mo...

This paper presents results of a failure data analysis of a LAN of Windows NT machines. Data for the study was obtained from event logs collected over a sixmonth period from the mail routing network of a commercial organization. The study focuses on characterizing causes of machine reboots. The key observations from this study are: (1) most of the problems that lead to reboots are software rela...

Statistical learning and sequential prediction are two different but related formalisms to study the quality of predictions. Mapping out their relations and transferring ideas is an active area of investigation. We provide another piece of the puzzle by showing that an important concept in sequential prediction, the mixability of a loss, has a natural counterpart in the statistical setting, whi...

Legislation controlling minimum floor space allowances for pigs rarely allows flexibility for variations in the physical and social environment. The space requirement of pigs housed in large groups and on deep-straw bedding has not been 2 adequately addressed. Pigs, housed on deep-straw for 6 weeks in groups of 20 or 80, were provided with a low (50 kg/m ) 2 or high (32 kg/m ) space allowance i...

The small-world phenomenon is found in many self-organising systems. Systems configured in small-world networks spread information more easily than in random or regular lattice-type networks. Whilst it is a known fact that small-world networks have short average path length and high clustering coefficient in self-organising systems, the ego centralities that maintain the cohesiveness of small-w...