Issues and Challenges in Current Technology for Engineering Self-Organising Applications

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1 AGENTCITIES TASK FORCE Issues and Challenges in Current Technology for Engineering Self-Organising Applications Agentcities Task Force Technical Note actf-note-xxxxx, 16 January, 2003 Authors (alphabetically): <<Author-name>>, <<Author-affiliation>> <<Author-name>>, <<Author-affiliation>> <<Author-name>>, <<Author-affiliation>> Copyright 2002 Agentcities Task Force (ACTF). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the ACTF or other organizations, except as needed for the purpose of developing Agentcities standards in which case the procedures for copyrights defined in the Agentcities Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the ACTF or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE AGENTCITIES TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Status Draft This version: Latest version: Abstract This document identifies technical problems with the current available techniques, which inhibit self-organising applications. ( ) 2002 Agentcities Task Force 1

2 Contents Agentcities Task Force Introduction Issues Agent-Level Issues Techniques Local Criteria Cellular Automata Utility-Based Socially-based behaviour Ant-like Human Societies Evolutionary Computation Applications Grid Business Process Infrastructure Networks Games and Simulations Robots AgentCities Taxonomy Case Studies Emergency Scenario Web Services Composition Challenges Conclusion References Change Log Version a: 15/01/ Agentcities Task Force 2

3 Introduction This document first reviews techniques currently in engineering self-organising applications; second, application domains, identified in document [], are analysed according to the technique(s) on which they are based and on several issues relevant to AgentCities. Finally, we discuss challenges that await the conceptual design of applications showing a selforganising behaviour. 2 Issues Engineering issues have been identified in the following two categories: agent-level issues related to individual components that form the application; and system level issues related to the application as a whole. 2.1 Agent-Level Issues Complexity (high/low): The different components that form a self-organising application can either have a low level of complexity, each single component is very simple, as it is the case for ants; or have a high level of complexity, as it it the case for the emergency scenario. Communication (direct/indirect): Communication among components of an SOA can occur either in a direct way, i.e., a component personally addresses messages to another component, or indirectly, i.e., a component operates changes in the environment, this changes will influence the behaviour of other components (stigmergy, context-awareness, ). Perspective (common/competitive): Components of an SOA have local goals, but they may have a common global goals, e.g., scientific people working for the same experiment; or may have competitive global goals, e.g., e-commerce applications. Purpose (goal/no goal) : A component can be goal-oriented or not. Discovery (yes/no): Agents may have or not the possibility to discover other agents. There are also cases where an agent that enters a system can know all agents in the system, but may remain unknown from them. This issue is also related to Web services/mobile services discovery. Heterogeneity (same kind/different kind): Components or agents of a SOA may all have the same capabilities, e.g., ants are all identical; or may have different capabilities, e.g., Web services, or components of the emergency scenario. 2.2 System-Level Issues Scalability (high/low): This issue is related to the ability of the application to scale to a large number of components. Reactivity (rapid/low): The global system may react rapidly or not to changes of the environment or to external pressures. Robustness (high/low): The global system may happen to be robust to external errors, or unforeseen situations. Robustness covers as well the high or low level of optimisation, resource management, and adaptability that the system can reach. Dynamicity of organisation (high/low): The self-organising structure may be easily or not able to reorganise itself at run-time, e.g., by changing groups, or through adaptability Agentcities Task Force 3

4 Security (vulnerable/not vulnerable): This issue measures to what extent the global system is vulnerable to non secure information, which can endanger or influence in some way the selforganising structure. Stability: Stability is a requirement for a self-organising application. It covers to time for the system to become stable, how long it remains stable, and the way how stability is reached (homogeneous; fixed periodic; chaotic; repeated patterns []). Hybrid (external/internal SO) : This issue is related to the way how the self-organising structure is perceived from the outside, i.e, if the observer is external or internal to the structure. Opened/Closed System: This issue is related to the global resulting system, if it is an opened or closed system. 3 Techniques Paper [Survey] explains mechanisms for realising a self-organising behaviour. Here, we explain computational techniques for engineering SOAs. 3.1 Local Criteria 3.2 Cellular Automata 3.3 Utility-Based 3.4 Socially-based behaviour Ant-like Human Societies 3.5 Evolutionary Computation 4 Applications 4.1 Grid Explain which technique(s) Grid-based applications adopt, and discuss each issue in this particular case Agentcities Task Force 4

5 Business Process Infrastructure Explain which technique(s) BPI applications adopt, and discuss each issue in this particular case. 4.3 Networks Explain which technique(s) Networking applications adopt, and discuss each issue in this particular case Agentcities Task Force 5

6 Games and Simulations Explain which technique(s) Games adopt, and discuss each issue in this particular case. 4.5 Robots 2002 Agentcities Task Force 6

7 AgentCities Explain which technique(s) AgentCities applications adopt, and discuss each issue in this particular case Agentcities Task Force 7

8 Taxonomy Local Criteria Cell. Automata Utility Based Social Evolutionary Complexity Comm. Perspective Purpose Discovery Heterogeneity Scalability Robustness Reactivity Dynamicity Security Stability Hybrid Open/Closed Grid BPI Networks Games/Sim. Robots AgentCities Table 1: Domains and Techniques Grid BPI Networks Games/Sim. Robots AgentCities Table 2: Domains and Issues Case Studies 5.1 Emergency Scenario (to be completed with: comment on the issues) 5.2 Web Services Composition (to be completed with: comment on the issues) 6 Challenges Summary of all what could be enhanced. Most likely it will be a list of points. 7 Conclusion Agentcities Task Force 8

9 References [<<ref>>] <<Title>>. <<Authors>>, <<Article/Organisation>>, <<Year>> Agentcities Task Force 9

10 Change Log 9.1 Version a: Page 1: Initial version 2002 Agentcities Task Force 10

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