Roberto Gagliardi

RUHEED-Rotated Unequal Clustering Algorithm for Wireless Sensor Networks

Prolonging the network lifetime, scalability and balancing are very important requirements when implementing a wireless sensor network (WSN). Clustering is a technique that has been widely applied for achieving these goals. However, there exists the energy hole problem which causes an unbalanced energy consumption in equally formed clusters. More specifically, nodes near the base station (BS) die very quickly since they, not only transmit their own data, but also forwards the rest of the network data. In this article, we propose a rotated unequal clustering protocol RUHEED in order to mitigate the energy hole problem. Our experiments show that RUHEED improves the network lifetime when compared to other clustering protocols.

Cloud computing for network business ecosystem

Traditionally, computing infrastructure has been a substantial burden for companies. But what happens when business are unchained from their physical infrastructure and allowed to focus on business goal ? The model of infrastructure as a service and cloud computing bring us closer to this possibility. In this paper we discussed the growth of the web based service industry. The myriad of service now available over the internet rely on data center spread around the world. One of the major new trends in computing the rise of what is known as cloud computing, in witch not only service are offered remotely over the internet, but also a full menu of computing resource such a computing power, storage, databases, and many other resources.

A Comparison of HEED Based Clustering Algorithms -- Introducing ER-HEED

A Wireless Sensor Network (WSN) is composed of distributed sensors with limited processing capabilities and energy restrictions. These unique attributes pose new challenges amongst which prolonging the WSN lifetime is one of the most important. Clustering is an energy efficient routing technique that has been widely applied to report data from the WSN nodes to a centralised Base Station. A plethora of different clustering protocols have been proposed. Some protocols are based on equal-sized clusters while others use clusters of unequal size. Some others make use of rotation techniques to reduce the amount of cluster head elections. When different clustering approaches are presented different simulation settings are used. In this paper we perform a comparison study of HEED based clustering protocols that are HEED, UHEED, RUHEED and a novel variation of R-HEED that is ER-HEED. We have considered the same network model, the same energy consumption model and we have compared the lifetime of the protocols by considering various case studies. Our comparison study shows that the selection of the protocol to be used depends on the case study and the WSN lifetime measure that is considered.

Deployment Challenges and Developments in Wireless Sensor Networks Clustering

Clustering techniques for wireless sensor networks (WSNs) have been extensively studied and proven to improve the network lifetime, a primary metric, used for performance evaluation of sensor networks. Although introduction of clustering techniques has the potential to reduce energy consumption and extend the lifetime of the network by decreasing the contention through either power control or node scheduling, scalability remains an issue. Therefore, the optimality of the cluster size still needs to be thoroughly investigated. In this paper, a single cluster head (CH) queuing model is presented. Using an event based simulation tool (Castalia), key issues that affect the practical deployment of clustering techniques in wireless sensor networks are analysed. These include identifying the bottlenecks in terms of cluster scalability and predicting the nature of data packets arrival distribution at the CH. Results presented show that this analysis can be used to specify the size of a cluster, when a specific flow of data is expected from the sensing nodes based on a particular application and also the distribution of the inter-arrival times of data packets at the CH follows exponential distribution.

On the fault tolerance of mobile ad hoc networks

In mobile ad hoc networks, it is crucial to reduce energy consumption satisfying key network properties. In this paper, we investigate the k-connected transmission power assignment problem with the objective of minimizing power consumption. We address this issue from a decision-theoretic point of view. Specifically, the future network behavior is predicted in order to derive an optimal transmission power assignment which tracks the wanted connectivity level minimizing energy.

Cloud for eGov: the state of the art

Specifically, the paper provides a detailed analysis of the state of the art regarding technological, regulatory and interoperability aspects, devoting particular attention to those projects (and related experience) in the field of cloud and distributed computing. The paper’s aim is to evaluate benefits and risks of the applicability of solutions that are already in place for the specified areas of interest. The key factors that determine relevant regulations, with particular emphasis on the European target, have been listed in the paper. Finally, the main Italian projects and the situation in some European countries have also been mentioned.

Business management and mobile experience

The large-scale access to content resources, the current change in the audience expectations, together with an underuse of the potentialities offered by mobile technology calls for a rethinking of the role of mobile interpretation within private and public business manager. Right in the in the area of intersection between business innovation and technology moves the paper, which deals, with the role of mobile technology in fostering learning and social engagement during the user experience. The main aim is indeed to provide developers with a framework able to guide a conscious design of content mobile experiences, fully exploiting the potentialities offered by this kind of technologies with clear objectives and the awareness of the means to achieve them. The spread of smartphones and tablets in the consumer market is having a big impact on the world of enterprise IT, with consumer-focused mobile devices making their way into the organization through the bring-your-own-device (BYOD) trend. One important aspect of coping with BYOD that is getting less attention, however, is the impact of employee data privacy legislation and how this creates constraints for IT managers implementing a BYOD policy. In this paper we have tried to provide answers to the many questions that innovation, business and mobile experience pose.