Contract Net Protocol

About: Contract Net Protocol is a research topic. Over the lifetime, 606 publications have been published within this topic receiving 13729 citations.

Multiagent Based Spectrum Sharing Using Petri Nets

Abstract: This paper presents a cooperative framework for dynamic spectrum access in cognitive radio networks, where the cognitive radio devices may use the currently unutilized spectrum dynamically and opportunistically. The proposed solution works on the principle of multiagent system that allows the cooperation amongst several participating devices. The key aspect of our design is the deployment of agents on each of the primary and cognitive radio device that cooperates in order to have a better and dynamic use of the spectrum. For cooperation, contract net protocol is considered allowing spectrum to be dynamically allocated by having a series of exchange of messages. Due to the concurrent, distributed and autonomous nature of our approach, Petri nets are adopted to model the behavior of cooperative framework. Based on Petri nets, we study the internal message passing and spectrum allocation mechanism between the participating primary and cognitive radio users and identify the information needed by the agents to make cooperative decisions. Then, using empirical results, we show that our approach achieves up to 80% of the whole utility within the span of few messages, and provides an effective mechanism for distributed spectrum allocation.

Retractable contract network for empowerment in workforce scheduling

Abstract: This paper is about business modelling and negotiation protocol design in distributed scheduling, where individual agents have individual (potentially conflicting) interests. It is motivated by BT's workforce scheduling problem, in which multiple service providers have to serve multiple service buyers. The service providers and buyers all attempt to maximize their own utility. The overall problem is a multi-objective optimization problem; for example, one has to maximize completion rates and service quality and minimize travelling distances. Although the work is motivated by BT's business operations, the aim is to develop a general negotiation protocol for staff empowerment. Standard contract net is a practical strategy in distributed scheduling where agents may have conflicting objectives. In this paper, we have introduced a retractable contract net protocol, RECONNET, which supports hill-climbing in the space of schedules. It is built upon a job-release and compensation mechanism. A system based on RECONNET has been implemented for BT's workforce scheduling problem. The software, which we call ASMCR, allows the management to exert full control over the company's multiple objectives. The manager generates a Pareto set of solutions by defining, for each buyer and seller, the weights given to each objective. ASMCR gives service buyers and sellers ownership of their problem and freedom to maximize their performance under the criteria defined by the management. ASMCR was tested on real-sized problems and demonstrated to meet BT's operational time requirement. It has full potential to be further developed for tackling BT's workforce scheduling problem.

Cooperative task assignment method of manned/unmanned aerial vehicle formation

Abstract: Task assignment method is an important part of task control process and plays a key role in formation cooperation C2.Based on contract net protocol(CNP) and multi-agent system(MAS) theory,MAS architecture and a bid based task assignment model of manned/unmanned aerial vehicle formation are built,and task priority is introduced into this model.The model can assign tasks in advance or in the process of mission running dynamically,which guarantees the overall assignment effectiveness relatively optimized in dynamic environment.Simulation results based on combat scenario indicate the task assignment method based on CNP and MAS behaves well in dynamic environment and can fulfill the requirements of formation combat.

A Verification by Abstraction Framework for organizational Multi-Agent Systems

Abstract: Software agents and multi-agent systems (MAS from now on) are recognized as both abstractions and eective technologies for modelling and building complex distributed applications. However, they are still dicult to engineer. The reason is that when massive number of autonomous components interact it is very dicult to predict that the emergent organizational structure fits the system goals or that the desired functionalities will be fulfilled. Verification approaches try to evaluate whether or not a product, service, or system complies with a specification. However verification approaches are limited by the state-space of the system under study. This paper proposes an approach based upon an organizational framework and specifically the capacity concept which enables to abstract a role know-how and to reduce the state space of the system under study. A formal framework based on multi-formalisms language and the specification approach are presented and illustrated through the specification of a part of the contract net protocol.