Heraclitus : a LFSR-based stream cipher with key dependent structure

We describe Heraclitus as an example of a stream cipher that uses a 128 bit index string to specify the structure of each instance in real time: each instance of Heraclitus will be a stream cipher based on mutually clocked shift registers. Ciphers with key-dependent structures have been investigated and are generally based on Feistel networks. Heraclitus, however, is based on mutually clocked shift registers. Ciphers of this type have been extensively analysed, and published attacks on them will be infeasible against any instance of Heraclitus. The speed and security of Heraclitus makes it suitable as a session cipher, that is, an instance is generated at key exchange and used for one session.

Trust ticket deployment : a notion of a data owner's trust in cloud computing

While cloud computing (CC) is a scalable model of shared infrastructure and on-demand computing, it lacks a transparent trust and security mechanism. A data owner (DO) loses control over the data outsourced to a machine in the cloud controlled and operated by a cloud service provider (CSP). This machine is at a location unknown to a data owner. This loss of control over data is further intensified with the lack of managing users' access to the data from practical cloud computing perspectives. In this paper, we introduce a new mechanism of ensuring trust and security in Software as a Service (SaaS) CC. Trust Ticket, with the supporting protocols, is our mechanism that helps a data owner in establishing a link between a CSP and a registered user. In our mechanism, a user first gets registered with a DO before receiving a Trust Ticket and a secret key from that DO. Each Trust Ticket is unique and encrypted. On completing the registration of each user, the DO apprises the CSP of the Trust Ticket. Trust Ticket and secret key are respectively for the registered user's getting accepted to the CSP and having a view of the data owner's data upon a successful verification by the CSP. We have done our experiment in Java network programming by creating an emulated cloud computing framework under the VMware ESXi 4.1 hyper visor based platform. Using the framework, we have evaluated our algorithmic protocol for Trust Ticket. We have also compared our work with prior work. Overall performance of our work is better. We argue that our proposed algorithmic protocol for Trust Ticket deployment establishes a data owner's trust. This trust is established through a data owner's control over data and a registered user, because a registered user is linked with a CSP by a data owner through Trust Ticket.

Enhancing cloud computing environments using a cluster as a service

The emergence of cloud computing has caused a significant change in how IT infrastructures are provided to research and business organizations. Instead of paying for expensive hardware and incur excessive maintenance costs, it is now possible to rent the IT infrastructure of other organizations for a minimal fee. While the existence of cloud computing is new. The elements used to create clouds have been around for some time. Cloud computing systems have been made possible through the use of large-scale clusters, service-oriented architecture (SOA), Web services, and virtualization. While the idea of offering resources via Web services is commonplace in cloud computing, little attention has been paid to the clients themselves specifically, human operators. Despite that clouds host a variety of resources which in turn are accessible to a variety of clients, support for human users is minimal.

Affect computing in film through sound energy dynamics

We develop an algorithm for the detection and classification of affective sound events underscored by specific patterns of sound energy dynamics. We relate the portrayal of these events to proposed high level affect or emotional coloring of the events. In this paper, four possible characteristic sound energy events are identified that convey well established meanings through their dynamics to portray and deliver certain affect, sentiment related to the horror film genre. Our algorithm is developed with the ultimate aim of automatically structuring sections of films that contain distinct shades of emotion related to horror themes for nonlinear media access and navigation. An average of 82% of the energy events, obtained from the analysis of the audio tracks of sections of four sample films corresponded correctly to the proposed affect. While the discrimination between certain sound energy event types was low, the algorithm correctly detected 71% of the occurrences of the sound energy events within audio tracks of the films analyzed, and thus forms a useful basis for determining affective scenes characteristic of horror in movies.

Cloud computing services : theoretical foundations of ethical and entrepreneurial adoption behaviour

Clouicomputing is an emerging service technology that has ethical and entrepreneurial implications. Due to technological innovations increasing the attention placed on cloud computing services, more people are focusing on the security and privacy issues determined by ethical guidelines and how the technology is evolving as an entrepreneurial service innov.ation. This paper presents a theoretical perspective on how a person adopts cloud computing. The literature on technology innovation and adoption behaviour is examined with a focus on social cognitive theory. A theoretical framework is then presented, which indicates a number of propositions to describe the intention of a person to adopt cloud computing services. The role of technology marketing capability, sustained learning and outcome expectancy are included in helping to understand the role of cloud computing applications. Suggestions for future research and practical implications are stated.

Computing of high breakdown regression estimators without sorting on graphics processing units

We present an approach to computing high-breakdown regression estimators in parallel on graphics processing units (GPU).We show that sorting the residuals is not necessary, and it can be substituted by calculating the median. We present and compare various methods to calculate the median and order statistics on GPUs. We introduce an alternative method based on the optimization of a convex function, and showits numerical superiority when calculating the order statistics of very large arrays on GPUs.

Modeling a dynamic data replication strategy to increase system availability in cloud computing environments

Failures are normal rather than exceptional in the cloud computing environments. To improve system avai-lability, replicating the popular data to multiple suitable locations is an advisable choice, as users can access the data from a nearby site. This is, however, not the case for replicas which must have a fixed number of copies on several locations. How to decide a reasonable number and right locations for replicas has become a challenge in the cloud computing. In this paper, a dynamic data replication strategy is put forward with a brief survey of replication strategy suitable for distributed computing environments. It includes: 1) analyzing and modeling the relationship between system availability and the number of replicas; 2) evaluating and identifying the popular data and triggering a replication operation when the popularity data passes a dynamic threshold; 3) calculating a suitable number of copies to meet a reasonable system byte effective rate requirement and placing replicas among data nodes in a balanced way; 4) designing the dynamic data replication algorithm in a cloud. Experimental results demonstrate the efficiency and effectiveness of the improved system brought by the proposed strategy in a cloud.