Simon Miles

The provenance of electronic data

It would include details of the processes that produced electronic data as far back as the beginning of time or at least the epoch of provenance awareness.

Electronically querying for the provenance of entities

The provenance of entities, whether electronic data or physical artefacts, is crucial information in practically all domains, including science, business and art. The increased use of software in automating activities provides the opportunity to add greatly to the amount we can know about an entitys history and the process by which it came to be as it is. However, it also presents difficulties: querying for the provenance of an entity could potentially return detailed information stretching back to the beginning of time, and most of it irrelevant to the querier. In this paper, we define the concept of provenance query and describe techniques that allow us to perform scoped provenance queries.

A Trace-Driven Analysis of Caching in Content-Centric Networks

A content-centric network is one which supports host-to-content routing, rather than the host-to-host routing of the existing Internet. This paper investigates the potential of caching data at the router-level in content-centric networks. To achieve this, two measurement sets are combined to gain an understanding of the potential caching benefits of deploying content-centric protocols over the current Internet topology. The first set of measurements is a study of the BitTorrent network, which provides detailed traces of content request patterns. This is then combined with CAIDAs ITDK Internet traces to replay the content requests over a real-world topology. Using this data, simulations are performed to measure how effective content-centric networking would have been if it were available to these consumers/providers. We find that larger cache sizes (10,000 packets) can create significant reductions in packet path lengths. On average, 2.02 hops are saved through caching (a 20% reduction), whilst also allowing 11% of data requests to be maintained within the requesters AS. Importantly, we also show that these benefits extend significantly beyond that of edge caching by allowing transit ASes to also reduce traffic.

The Requirements of Using Provenance in e-Science Experiments

In e-Science experiments, it is vital to record the experimental process for later use such as in interpreting results, verifying that the correct process took place or tracing where data came from. The process that led to some data is called the provenance of that data, and a provenance architecture is the software architecture for a system that will provide the necessary functionality to record, store and use process documentation to determine the provenance of data items. However, there has been little principled analysis of what is actually required of a provenance architecture, so it is impossible to determine the functionality they would ideally support. In this paper, we present use cases for a provenance architecture from current experiments in biology, chemistry, physics and computer science, and analyse the use cases to determine the technical requirements of a generic, technology and application-independent architecture. We propose an architecture that meets these requirements, analyse its features compared with other approaches and evaluate a preliminary implementation by attempting to realise two of the use cases.

Towards a Formalisation of Electronic Contracting Environments

Clauses within contracts may be thought of as norms, specifying permissions, obligations and prohibitions on contract parties. In this paper, we present a formal representation of contracts, focusing on the specification of a model of norms. With this model, a norm is associated with a status, which may change as the environment, and the status of other norms, changes. We define a normative environment, which may be used to track the status of a set of norms throughout their lifecycle, and then describe a predicates that may be used to evaluate a norms status. Agents are able to use these predicates to reason about the status of norms, and how their actions will affect the normative environment. Finally, we show the applicability of our framework to real world domains by monitoring the execution of a contract taken from a real world scenario.

Transparent Fault Tolerance for Web Services Based Architectures

Service-based architectures enable the development of new classes of Grid and distributed applications. One of the main capabilities provided by such systems is the dynamic and flexible integration of services, according to which services are allowed to be a part of more than one distributed system and simultaneously serve different applications. This increased flexibility in system composition makes it difficult to address classical distributed system issues such as fault-tolerance. While it is relatively easy to make an individual service fault-tolerant, improving fault-tolerance of services collaborating in multiple application scenarios is a challenging task. In this paper, we look at the issue of developing fault-tolerant service-based distributed systems, and propose an infrastructure to implement fault tolerance capabilities transparent to services.

Automating experiments using semantic data in a bioinformatics grid

The transition from laboratory science to in silico e-science has facilitated a paradigmatic shift in the way we conduct modern science. We can use computationally based analytical models to simulate and investigate scientific questions such as those posed by high-energy physics and bioinformatics, yielding high-quality results and discoveries at an unprecedented rate. However, while experimental media have changed, the scientific methodologies and processes we choose for conducting experiments are still relevant. As in the lab environment, experimental methodology requires samples to undergo several processing stages. The staging of operations is what constitutes the in silico experimental process. The use of workflows formalizes earlier ad hoc approaches for representing experimental methodology. We can represent the stages of in silico experiments formally as a set of services to invoke.

Security issues in a SOA-Based provenance system

Recent work has begun exploring the characterization and utilization of provenance in systems based on the Service Oriented Architecture (such as Web Services and Grid based environments). One of the salient issues related to provenance use within any given system is its security. Provenance presents some unique security requirements of its own, which are additionally dependent on the architectural and environmental context that a provenance system operates in. We discuss the security considerations pertaining to a Service Oriented Architecture based provenance system. Concurrently, we outline possible approaches to address them.

PrIMe: A methodology for developing provenance-aware applications

Provenance refers to the past processes that brought about a given (version of an) object, item or entity. By knowing the provenance of data, users can often better understand, trust, reproduce, and validate it. A provenance-aware application has the functionality to answer questions regarding the provenance of the data it produces, by using documentation of past processes. PrIMe is a software engineering technique for adapting application designs to enable them to interact with a provenance middleware layer, thereby making them provenance-aware. In this article, we specify the steps involved in applying PrIMe, analyze its effectiveness, and illustrate its use with two case studies, in bioinformatics and medicine.

Provenance in Agent-Mediated Healthcare Systems

People are increasingly cooperating to share electronic information and techniques throughout various industries. In healthcare applications, data (a single patients healthcare history), workflow (procedures carried out on that patient), and logs (a recording of meaningful procedural events) are often distributed among several heterogeneous and autonomous information systems. Understanding a patients treatment history can help healthcare providers make treatment decisions. Provenance-aware applications can facilitate this process by tracing events, event dependencies, and provider decisions across various healthcare institutions