CatNet: Catallactic mechanisms for service control and resource allocation in large-scale application-layer networks

Collaborative tools based on the Web/Internet infrastructure such as E-mail, discussion groups, video/audio conferencing and virtual campuses have been proposed and implemented in many distance learning scenarios. Grids as Internet-wide resource infrastructures that enable access to large resource pools should permit new applications and learning activities. We propose ULabGrid as a new architecture that enables educators to design collaborative, distant laboratories for undergraduate students using the Grid infrastructure. We describe here the prototype that is being developed and present the results of our efforts to date.Peer Reviewe

Integration of decentralized economic models for resource self-management in application layer networks

Resource allocation is one of the challenges for self-management of large scale distributed applications running in a dynamic and heterogeneous environment. Considering Application Layer Networks (ALN) as a general term for such applications including computational Grids, Content Distribution Networks and P2P applications, the characteristics of the ALNs and the environment preclude an efficient resource allocation by a central instance. The approach we propose integrates ideas from decentralized economic models into the architecture of a resource allocation middleware, which allows the scalability towards the participant number and the robustness in very dynamic environments. At the same time, the pursuit of the participants for their individual goals should benefit the global optimization of the application. In this work, we describe the components of this middleware architecture and introduce an ongoing prototype.Peer Reviewe

Performance measuring framework for grid market middleware

Current implementations of Grid infrastructures provide frameworks which aim at achieve on-demand computing. In such a scenario, contribution and use of resources will be governed by business models. The challenge is to provide multi-level performance information which enables the participation of the different actors in such a system. In this paper we describe the performance measuring framework developed for Grid Market Middleware, a middleware which supports economic-model based selection of service-oriented Grid applications. This middleware is a distributed infrastructure, which we have implemented for providing a market of services and resources to be assigned to Grid applications. The objectives of the performance measuring framework is first to assess the behaviour of the middleware and the used economic models in a deployed system, and secondly allow the provision of metrics for the components of the middleware itself. We describe the design of the performance measuring framework, its implementation and show its capability and usefulness for our objectives by experiments.Peer Reviewe

Decentralized resource allocation in application layer networks

Application-layer networks (ALN) are software architectures that allow the provisioning of services requiring a huge amount of resources by connecting large numbers of individual computers. The ALN simulation project CATNET evaluates a decentralized mechanism for resource allocation in ALN, which is based on the economic paradigm of the Catallaxy, against a centralized mechanism using an arbitrator object. In both versions, software agents buy and sell network services and resources to and from each other. The economic model is based on self-interested maximization of utility and self-interested cooperation between agents. This article describes the design of money and message flows for centralized and decentralized coordination in both versions and shows preliminary results.Peer Reviewe

Self-organizing resource allocation for autonomic networks

Application-layer networks (ALN) are software architectures that allow the provisioning of services requiring a huge amount of resources by connecting large numbers of individual computers, e.g. grids and P2P-Networks. Self-organization, like proposed by the autonomic computing concept, might be the key to controlling these systems. The CATNET project evaluates a decentralized mechanism for resource allocation in ALN, based on the economic paradigm of the Catallaxy. The economic model is based on self-interested maximization of utility and self-interested cooperation between software agents, who buy and sell network services and resources to and from each other.Peer Reviewe

A catallactic market for data mining services.

We describe a Grid market for exchanging data mining services based on the Catallactic market mechanism proposed by von Hayek. This market mechanism allows selection between multiple instances of services based on operations required in a data mining task (such as data migration, data pre-processing and subsequently data analysis). Catallaxy is a decentralized approach, based on a “free market” mechanism, and is particularly useful when the number of market participants is large or when conditions within the market often change. It is therefore particularly suitable in Grid and peer-2-peer systems. The approach assumes that the service provider and user are not co-located, and require multiple message exchanges to carry out a data mining task. A market of J48-based decision tree algorithm instances, each implemented as a Web service, is used to demonstrate our approach. We have validated the feasibility of building catallactic data mining grid applications, and implemented a proof-of-concept application (Cat-COVITE) mapped to a Catallactic Grid Middleware.Peer Reviewe

Exploring the catallactic coordination approach for peer-to-peer systems

Efficient discovery and resource allocation is one of the challenges of current Peer-to-Peer systems. In centralized approaches, the user requests can be matched to the fastest, cheapest or most available resource. This approach, however, shows scalability limits. In this paper, we explore the catallactic coordination as a decentralized economic approach for resource allocation in peer-topeer networks. The economic model of the catallaxy is based on the selfinterested maximization of utility and the negotiation of prices between agents. We evaluate the feasibility of our approach by means of simulations and compare the proposed system with a centralized baseline approach. Our results indicate that while in the catallacic approach the number of control messages exchanged between the peers grows due to the negotiation process, its service provision rate is fairly constant in different dynamic environments.Peer Reviewe

ULabGrid, an infrastructure to develop distant laboratories for undergrad students over a Grid

Nowadays, there is a big discussion about two different topics: how distance learning and the old fashioned learning can be improved using the new technologies. In both cases, there are many collaborative tools based on the web infrastructure such as e-mail, web discussing groups, virtual campuses or audio and video conferences, that basically give a way of exchanging information among the different groups involved in learning tasks, but very few of them have been thought to help or to develop laboratory classes (labs). In this paper we describe a GRID infrastructure (ULabGrid) that supports distant laboratories for undergrad students.Peer Reviewe

Decentralized vs. centralized economic coordination of resource allocation in grids

Application layer networks are software architectures that allow the provisioning of services requiring a huge amount of resources by connecting large numbers of individual computers, like in Grid or Peer-to-Peer computing. Controlling the resource allocation in those networks is nearly impossible using a centralized arbitrator. The network simulation project CATNET will evaluate a decentralized mechanism for resource allocation, which is based on the economic paradigm of the Catallaxy, against a centralized mechanism using an arbitrator object. In both versions, software agents buy and sell network services and resources to and from each other. The economic model is based on self-interested maximization of utility and self-interested cooperation between agents. This article describes the setup of money and message flows both for centralized and decentralized coordination in comparison.Peer Reviewe

An electrochemical investigation of erosion corrosion of duplex stainless steel in sea water containing sand particles

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