Cloud computing is rapidly changing the digital service landscape. A proliferation of Cloud providers has emerged, increasing the difficulty of consumer decisions. Trust issues have been identified as a factor holding back Cloud adoption. The risks and challenges inherent in the adoption of Cloud services are well recognised in the computing literature. In conjunction with these risks, the relative novelty of the online environment as a context for the provision of business services can increase consumer perceptions of uncertainty. This uncertainty is worsened in a Cloud context due to the lack of transparency, from the consumer perspective, into the service types, operational conditions and the quality of service offered by the diverse providers. Previous approaches failed to provide an appropriate medium for communicating trust and trustworthiness in Clouds. A new strategy is required to improve consumer confidence and trust in Cloud providers. This paper presents the operationalisation of a trust label system designed to communicate trust and trustworthiness in Cloud services. We describe the technical details and implementation of the trust label components. Based on a use case scenario, an initial evaluation was carried out to test its operations and its usefulness for increasing consumer trust in Cloud services.

The purpose of this research is to identify the potential information components of an online, real-time trust label, which is proposed as a communication mechanism to encourage trust in cloud service providers and cloud computing products. An online Delphi process was used with 28 cloud computing experts (including vendors, software providers, and legal and business representatives). The proposed label contains 81 information components, covering the cloud service provider (e.g. physical location, legal jurisdiction), the cloud service itself (e.g. data location, security, backup, certification), and a historical service-level summary (e.g. uptime data, support response times). The potential benefits of such a label to encourage trustworthiness perceptions and trust behaviors in the cloud computing environment are explored. Limitations of the study are highlighted, and further research studies are suggested to test the concept of the label and to refine the components of the label itself.

A data location control model for Cloud services is presented that uses an authorization system as its core control element. The model is intended for use by enterprises that collect personal data from end users that can potentially be stored and processed at multiple geographic locations. By adhering to the model's authorization decisions, the enterprise can address end users' concerns about the location of their data by incorporating the their preferences about the location of their personal data into authorization policy. The model also ensures that the end users have visibility into the location of their data and are informed when the location of their data changes. A prototype of the model has been implemented that provides the data owner with an interface that allows their location preferences to be expressed. These preferences are stored internally as XACML policy documents. Thereafter, movements or remote duplications of the data must be authorized by submitting requests to an ISO/IEC 10181-3:1996 compliant Policy Enforcement Point. End users can, at any time, view up-to-date information on the locations where their data is stored via a web interface. Furthermore, XACML obligations are used to ensure that end users are informed whenever the location of their data changes.

Bid-centric service descriptions have the potential to offer a new cloud service provisioning model that promotes portability, diversity of choice and differentiation between providers. A bid matching model based on requirements and capabilities is presented that provides the basis for such an approach. In order to facilitate the bidding process, tenders should be specified as abstractly as possible so that the solution space is not needlessly restricted. To this end, we describe how partial TOSCA service descriptions allow for a range of diverse solutions to be proposed by multiple providers in response to tenders. Rather than adopting a lowest common denominator approach, true portability should allow for the relative strengths and differentiating features of cloud service providers to be applied to bids. With this in mind, we describe how service descriptions can be augmented with additional information that allows the bid matching algorithm to make use of heterogeneous processing resources, such as GPUs and MICs.

The processing of a patient in a medical facility encompasses data acquisition, data analysis, diagnosis and medical reporting. The result is a program of treatment for the patient. It is postulated that the latter two stages can be facilitated by allowing acquisition locations to avail of data interpretation by multiple off-site analysts who interactively annotate patient data in a collaborative fashion. The concept of “meta annotations” is also introduced, whereby users can comment on an annotation or supply a confidence rating that indicates their assessment of the accuracy of an annotation. This concept enhances the utility of annotations by transforming them from simple textual labels to focal points for discussion and consensus building.

WebCom is a metacomputer based on the Condensed Graphs model of computing. Within this model, applications are represented as directed acyclic graphs with the nodes representing tasks and arcs their sequencing constraints. This paper presents the job management system used in WebCom. We describe the techniques required to apply common job management concepts, such as suspension, migration and monitoring, to the execution of applications expressed as Condensed Graphs.

The use of application-specific co-processors created using reconfigurable hardware (FPGAs) has been shown to realize significant speed increases for many computationally intensive applications. The addition of reconfigurable hardware to clusters composed of commodity machines in order to improve the execution times of parallel applications would, therefore, appear to be a logical step. However, the extra complications introduced by this technique may make the real-world application of such technology appear to be prohibitively difficult. In this paper the design and implementation of a metacomputer designed to simplify the development of applications for clusters containing re-configurable hardware are presented. The operation of the metacomputer is also discussed in some detail, including the process of implementing applications for execution on the metacomputer.