An adaptive and trustworthy software testing framework on the grid

Grid computing, which is characterized by large-scale sharing and collaboration of dynamic distributed resources has quickly become a mainstream technology in distributed computing and is changing the traditional way of software development. In this article, we present a grid-based software testing framework for unit and integration test, which takes advantage of the large-scale and cost-efficient computational grid resources to establish a testbed for supporting automated software test in complex software applications. Within this software testing framework, a dynamic bag-of-tasks model using swarm intelligence is developed to adaptively schedule unit test cases. Various high-confidence computing mechanisms, such as redundancy, intermediate value checks, verification code injection, and consistency checks are employed to verify the correctness of each test case execution on the grid. Grid workflow is used to coordinate various test units for integration test. Overall, we expect that the grid-based software testing framework can provide efficient and trustworthy services to significantly accelerate the testing process with large-scale software testing.

A grouped P2P network for scalable grid information services

Information services play a crucial role in grid environments in that the state information can be used to facilitate the discovery of resources and the services available to meet user requirements, and also to help tune the performance of a grid system. However, the large size and dynamic nature of the grid brings forth a number of challenges for information services. This paper presents PIndex, a grouped peer-to-peer network that can be used for scalable grid information services. PIndex builds on Globus MDS4, but introduces peer groups to dynamically split the large grid information search space into many small sections to enhance its scalability and resilience. PIndex is subsequently modeled with Colored Petri Nets for performance evaluation. The simulation results show that PIndex is scalable and resilient in dealing with a large number of peer nodes.

Services computing as the foundation of enterprise agility: Overview of recent advances and introduction to the special issue

The advancement of web services in the last few years has spurred a number of revolutionary concepts in information technology and management including service-oriented architectures, service-oriented computing, and services science, management and engineering, which can be collectively called as “services computing.” Services computing is a new research field that goes beyond traditional computing disciplines as it includes not only architectural, programming, deployment, and other engineering issues, but also management issues such as business component modeling, business process design, and service delivery. In this paper, we provide an overview of emerging research concepts in services computing without attempting to unify them as it will take sometime for the field to become mature. In addition, we take a position that the ultimate goal of services computing is to create the necessary technological and managerial foundation to support enterprise agility. In this short paper, we give an overview of services computing, describe its relationship to enterprise agility, and discuss basic technical and managerial issues. Finally, we introduce the papers that are published in this special issue.

Understanding and measuring the urban pervasive infrastructure

The increasing popularity of mobile computing devices has allowed for new research and application areas. Specifically, urban areas exhibit an elevated concentration of such devices enabling potential ad-hoc co-operation and sharing of resources among citizens. Here, we argue that people, architecture and technology together provide the infrastructure for these applications and an understanding of this infrastructure is important for effective design and development. We focus on describing the metrics for describing this infrastructure and elaborate on a set of observation, analysis and simulation methods for capturing, deriving and utilising those metrics.

IPBGA: a hybrid P2P based grid architecture by using information pool protocol

The current representatives of Grid systems are Globus and Web services, however, they have poor scalability and single point failure. It is these two factors which make the building of an improved P2P and grid hybrid framework for resource management and task schedule such a popular research topic. This paper differs from current research because it puts forward an Information Pool Based Grid Architecture (IPBGA), which is a real sense hybrid of P2P and grid instead of only introducing P2P methods into grid systems for resource management. Based on virtualizations, abstract physical resources and tasks to be, the information requests from resources for tasks and appeals from tasks for resources are upgraded as information services by using an information pool protocol (IPP). Thus, grid resource management and task scheduling are regarded as information matching by IPP which is adaptive to the heterogeneous, dynamic, and distributed characteristics of a grid system. Tri-Information Center (Tri-IC) and source ranking mechanisms are presented in IPP to improve robustness, prevent sybil attack, and to discourage free riding. Experiments and theory analysis show that the IPP of the IPBGA is more efficient and robust in dealing with information while both the bandwidth and process costs are less.

On the universality of peptide computing

We present a simulation of Turing machines by peptide–antibody interactions. In contrast to an earlier simulation, this new technique simulates the computation steps automatically by the interaction between peptides and antibodies and does not rely on a “look-and-do” approach, in which the Turing machine program would be interpreted by an extraneous computing agent. We determine the resource requirements of the simulation. Towards a precise definition for peptide computing we construct a new theoretical model. We examine how the simulations presented in this paper fits this model. We also give conditions on the peptide computing model so that it can be simulated by a Turing machine.

Evolving a pervasive IT infrastructure: a technology integration approach

Over the past five years or so, pervasive computing has emerged as a new computing paradigm with a great deal of appeal. Enterprises are increasingly showing interest in deploying pervasive information technology (IT) infrastructures to realise the perceived benefits offered by this new computing paradigm. However, a return on the investment and considerations of the currently deployed infrastructure is a constraint for businesses to invest in a pervasive IT infrastructure. Realising that the economics of an investment in a new infrastructure can affect the embracing of pervasive IT, we suggest an approach that shows how the existing technology solutions available in the market and deployed in an enterprise can be used to develop a pervasive IT infrastructure, thereby protecting investments and maximising returns. We present an evolution model to systematically and incrementally achieve a pervasive IT environment, and present guidelines for evaluating which services to develop first based on evolving the existing infrastructure point of view. This work provides practical implications for enterprises as well as pointers for research.

Relooking at services science and services innovation

In lots of countries, service economy has become the dominant economy. Modern services industries require talents skillful at multidiscipline subjects including IT services, business models, management skills, psychology, etc. There is the rise of services science, service-oriented computing, and services computing. The multidiscipline features bring new challenges for services science. In this paper, we go beyond the traditional view of services and propose a three-layer framework for services science and services innovation. The framework covers service needs, service competencies, and service resources. We believe that these are the common building blocks and foundations for modern services industries. We use Amazon as an example to show the relevant of the framework for analyzing patterns of services innovation. We also use this framework to derive a set of service curricula for training talents for modern services.

Activity-based computing: support for mobility and collaboration in ubiquitous computing

This paper presents the design philosophy of activity-based computing (ABC), which addresses mobility and cooperation in human work activities. Furthermore, it presents the ABC framework, which is a ubiquitous computing infrastructure supporting ABC. The idea of ABC and the aim of the ABC framework is to: (1) support human activity by managing its collection of work tasks on a computer, (2) support mobility by distributing activities across heterogeneous computing environments, (3) support asynchronous collaboration by allowing several people to participate in an activity, and (4) support synchronous, real-time collaboration by enabling desktop conferencing by sharing the activity across several clients. During a period of two years, the ABC framework has been co-designed and evaluated in close cooperation with a range of clinicians in a hospital.

On string languages generated by spiking neural P systems with exhaustive use of rules

We continue the study of (extended) spiking neural P systems with exhaustive use of rules by considering these computing devices as language generators. Specifically, a step is associated with a symbol according to the number of spikes emitted by the output neuron and the sequence of these symbols associated with a halting computation constitutes a string. Two cases are considered: one of them interprets a step when no spike is emitted as a specified symbol, the other interprets such a step as the empty string. In both cases, it is proved that finite and recursively enumerable languages are characterized by extended spiking neural P systems working in the exhaustive mode. The relationships with regular languages are also investigated.

Reverse engineering relational databases to identify and specify basic Web services with respect to service oriented computing

Service-oriented computing (SOC) is the computing paradigm that utilizes services as a fundamental building block. Services are self-describing, open components intended to support composition of distributed applications. Currently, Web services provide a standard-based realization of SOC due to: (1) the machine-readable format (XML) of their functional and nonfunctional specifications, and (2) their messaging protocols built on top of the Internet. However, how to methodologically identify, specify, design, deploy and manage a sound and complete set of Web services to move to a service-oriented architecture (SOA) is still an issue. This paper describes a process for reverse engineering relational database applications architecture into SOA architecture, where SQL statements are insulated from the applications, factored, implemented, and registered as Web services to be discovered, selected, and reused in composing e-business solutions. The process is based on two types of design patterns: schema transformation pattern and CRUD operations pattern. First, the schema transformation pattern allows an identification of the services. Then the CRUD operations pattern allows a specification of the abstract part of the identified services, namely their port types. This process is implemented as a CASE tool, which assists analysts specifying services that implement common, reusable, basic business logic and data manipulation.

Trustworthy remote compiling services for grid-based scientific applications

Grid computing, which is characterized by large-scale sharing and collaboration of dynamic resources, is becoming an emerging computing platform on a global scale for data-intensive and computation-intensive scientific application. However, the complications of large-scale scientific computations and simulations harnessing massive computing resources are compounded by extensive heterogeneity in environments arising from “the Grid.” Scientists and engineers lack an intuitive grid-based compilation tool, which has contributed to the difficulty of exploiting these diverse resources and developing their applications on the grid. While manual configuration of various toolkits simplifying the end-to-end completion of a job is adequate for a computational grid with a limited number of nodes, the compilation procedure becomes inefficient for a computational grid with an increasing number of heterogeneous computational service providers. On the other hand, a global-scale computational grid is a potentially untrustworthy computing environment. How to take advantage of the potentially untrustworthy grid resources to provide trustworthy computational services for large-scale scientific applications is another critical issue. In this article, a remote compiling service for a heterogeneous computational grid is developed. In addition to running compilation tasks, the remote compiling service provides security enforcement and validation facilities, including intermediate value checking, secure source program submission, restricted compilation, and binary inspection, to support trustworthy compilation and execution of grid-based scientific applications. Overall, it is expected that our remote compiling services on the grid can tackle the heterogeneity problem of the grid and provide a secure, trustworthy, reliable, and state-of-the-art mechanism to develop grid-aware scientific applications.

An application of a context-aware file system

Ubiquitous computing environments stretch the requirements of traditional infrastructures used to facilitate the development of applications. Activities are often supported by collections of applications, some of which are automatically launched with little or no human intervention. This task-driven environment challenges existing application construction and data management techniques. In this paper, we describe a file system that organises application data based on contextual information, imports user data based on its physical presence, and supports format conversions to accommodate device context. We describe several applications that we have developed within our ubiquitous computing infrastructure and show how they leverage the novel features of our file system to simplify their complexity.

Agent-mediated knowledge sharing for intelligent services management

For service-oriented architectures that span multiple businesses, organizations must transfer information back-and-forth about their available services. Because of the potential large volume, it is unreasonable and impractical to expect human practitioners to handle the scale of interactions desired and/or required on a continual basis. Intelligent agents offer the adaptability and flexibility to handle the knowledge transfer that must occur in order to share service offerings. Effectively transferring service-oriented information in this domain requires autonomous systems that adapt to heterogeneous environments. This work introduces an architecture and specialized communication procedures designed for this sort of knowledge sharing environment. We show that these procedures perform reasonably when evaluated with current agent communication technologies.

A Service Oriented Architecture-based Approach for Interdomain Optical Network Services

This work presents a service-oriented architecture for interdomain service provisioning in optical networks. The architecture introduces a service layer that concentrates all the interactions among domains necessary for service provisioning. A service layer is an alternative to the GMPLS (Generalized Multiprotocol Label Switching) architecture, but without a rigid control plane as found in GMPLS. We start by defining a set of basic services to provide single end-to-end (e2e) interdomain connections. Then, more sophisticated services are created through the composition of these basic services. The interdomain Optical VPN (Virtual Private Network) service is considered in order to illustrate the composition of services. A prototype of the architecture was designed and implemented using Web services as the main technology. The architecture was evaluated in terms of speed, scalability, and bandwidth consumption necessary to establish e2e interdomain connections and Optical VPNs.

Defining the grid: a snapshot on the current view

The term “Grid” was introduced in early 1998 with the launch of the book “The Grid. Blueprint for a new computing infrastructure”. Since that time many technological changes have occurred in both hardware and software. One of the most important ones seems to be the wide acceptance of Web services. Although the basic Grid idea has not changed much in the last decade, many people have different ideas about what a Grid really is. In the following article we report on a survey where we invited many people in the field of Grid computing to give us their current understanding.

Quantum Algorithms: Philosophical Lessons

I discuss the philosophical implications that the rising new science of quantum computing may have on the philosophy of computer science. While quantum algorithms leave the notion of Turing-Computability intact, they may re-describe the abstract space of computational complexity theory hence militate against the autonomous character of some of the concepts and categories of computer science.

The design and implementation of Visuel performance monitoring and analysis toolkit for cluster and grid environments

The computing power provided by high performance and low-cost PC-based clusters with Grid platforms are attractive and they are equal or superior to supercomputers and mainframes. In this paper, we present implementation and design rationale of Visuel toolkit for MPI parallel program performance measurement and analysis in cluster and grid environments. Most of performance visualization tools available today for high-performance platforms show solely system performance data (e.g., CPU load, memory usage, network bandwidth, server average load), and thus, being suitable for computing system activity visualization. The Visuel (Visuel (in French language) = to visualize) toolkit is web-based interface designed to show performance activities of all computing nodes of a distributed environment involved in the execution of MPI parallel program, such as CPU load level and memory usage of each computing node. In addition, this toolkit is able to display comparative performance data charts of MPI parallel applications and multiple executions under investigation. The usage of this toolkit shows that it outperforms in easing the process of investigation of parallel applications.

A survey on peer-to-peer video streaming systems

Video-over-IP applications have recently attracted a large number of users on the Internet. Traditional client-server based video streaming solutions incur expensive bandwidth provision cost on the server. Peer-to-Peer (P2P) networking is a new paradigm to build distributed network applications. Recently, several P2P streaming systems have been deployed to provide live and on-demand video streaming services on the Internet at low server cost. In this paper, we provide a survey on the existing P2P solutions for live and on-demand video streaming. Representative P2P streaming systems, including tree, multi-tree and mesh based systems are introduced. We describe the challenges and solutions of providing live and on-demand video streaming in P2P environment. Open research issues on P2P video streaming are also discussed.