Jiří Hodík

Communication security in multi-agent systems

Both, research and application development in the area of multi-agent systems currently undertakes rapid expansion. In order to use multi-agent technology in real applications, it is inevitable to ensure security, integrity and authenticity of inter-agent communication. Various securitysystems, developed for different applications have been used in multi-agent system (MAS). Alternatively, MAS are designed with respect to the specific communication security requirements. This paper describes the architecture and implementation of the security (X-Security) system, which implemets authentication and secure communication among agents. System uses certification authority (CA) and ensures full cooperation of secured agents and already existing (unsecured) agents. Principle of the system integration into already existing MAS is described here as well as possibility of its usage for mobile agents. Paper deals as well with security mechanisms activity during inaccessibility of CA and possibility of CAs recreation. Security system was designed according the FIPA standards.

Vo Management Solutions VO Management e-Services

A virtual organization is usually considered to be a set of cooperating independent entities, which to the outside world provides a set of services and functionality as if they were one organization. Virtual organization management denotes the organisation, allocation and co-ordination of resources and their activities as well as their inter-organisational dependencies to achieve the objectives within the required time, cost and quality frame. Collaboration and management therefore have to be tackled by provision of adequate methods and services for the single users involved, in dependence of their roles and profiles within the network. Based on the outlined results described in the previous 2 Chapters the following chapter concentrates on the description of e-Services as Solutions for Virtual Organization management.

Competitive Contract Net Protocol

The proposed Competitive Contract Net Protocol has been designed to facilitate a flexible cooperation in competitive multi-agent environments and to support automated or semi-automated negotiations in competitive domains. The protocol is based on FIPA standards. The protocol covers not only the phase of contracting the commitments, but also allows for a decommitment negotiation and contract termination. Thus, it consists of three phases: (i) a contracting phase, where conditions of agreement are concluded, (ii) an optional decommitment phase, where contract may be breached, and (iii) a contract termination phase, where the compliance with the concluded contract conditions is evaluated. Both the decommitment and non-compliance are bounded with penalties which measurably ensure a compliance with the commitments, but also allow an opportunistic behaviour of the agents at some price.

Competencies and Profiles Management for Virtual Organizations Creation

Sharing information about profiles and offered competencies of individual members within an alliance of cooperating companies facilitates searching for potential members of Virtual Organizations. This paper presents a concept of structuring of the competencies as well as a prototype proving this concept. The prototype follows a naturally hybrid architecture of alliances that consists of mutually independent alliance partners, who may be supported by central institutions of the alliance. The use of the agent-based solution enables information sharing among partners in such distributed and dynamic environment.

Agent Exchange – Virtual Trading Environment

Agent Exchange is a virtual trading environment serving as a test bed for experiments with market simulations, trading strategies and auctioning techniques. Agent Exchange is the distributed environment implementing up-to-date knowledge from multi-agent systems and secure communication. The developed agent community consists of independent agents communicating via defined protocols and ontology. The secure agent communication is an important part of this project. Roles that agents can play in the Agent Exchange community are Trading-agent, Bank-agent, Exchange-agent, Scenario-agent, User-agent, and Central treading authority agent. This paper describes the design of the Agent Exchange project, its functions and implementation details.

Creation of Robust Schedule for Profit Based Cooperation

Method for robust schedule preparation for domain of profit based cooperation is introduced in this paper. The method aims schedules, which are prepared and concluded step-by-step during the team formation phase. The method takes into account domain specifics, like incomplete information about the partners, and their various reputation and skill levels. The method is based on critical path dispatching rule, which is widely used in heuristics for np hard and continuous scheduling problems. Experimental results are presented for various workflow structures and other configurations of the domain.