1. Providing Updated Contextual Information for Norm-Aware Agents in Open MASs Carolina Howard Felicíssimo LES-PUC-Rio / LIP6-ParisVI Advisor: Prof. Carlos José Pereira de Lucena Co-Advisor: Prof. Jean-Pierre Briot

2. August 17, 2007 2/28 Carolina Howard Felicíssimo © LES/PUC-Rio Motivation Support the Development of Normative Open Multi-Agent Systems Support Norm-Aware Agents with Updated Contextual Information Our approach: DynaCROM (dynamic contextual regulation information provision in open MASs)

3. August 17, 2007 3/28 Carolina Howard Felicíssimo © LES/PUC-Rio Agenda Introduction DynaCROM DynaCROM at Work Related Work Conclusion

4. August 17, 2007 4/28 Carolina Howard Felicíssimo © LES/PUC-Rio Introduction We assume that MASs are open systems In Open MASs, agents can freely migrate among them in order to obtain resources or services not found locally -> Open MASs are Extremely Dynamics ! Key characteristics of open systems are: –Heterogeneity –Conflicting Individual Goals –Limited Trust Agents’ actions may deviate from the expected behavior Openness has led to software systems that have no centralized control

5. August 17, 2007 5/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Current Implemented Architecture Normative behavior DynaCROM JADE Agent Architecture

6. August 17, 2007 6/28 Carolina Howard Felicíssimo © LES/PUC-Rio Enabling Heterogeneous Agents to Perform in a DynaCROM MAS (1) public class ExternalAgent extends Agent{... (2) protected void setup(){ (3) addBehaviour(new DynaCROM(this, “APintelSupplier”, “computer-supplier”)); (4)... } (1) public abstract class PlanForSuppliers extends APlanForASimpleFIPAContractNetIProtocol {... (2) public abstract Object[] makeAProposal( String productItem, String productQuantity, String contextualCurrency); //Must return a collection of objects with // [String currency, String proposedPrice] (3)... } DynaCROM makeAProposal() ASupplierAgent

7. August 17, 2007 7/28 Carolina Howard Felicíssimo © LES/PUC-Rio Enabling Heterogeneous Agents to Perform in a DynaCROM MAS (1) public void action(){... (2) receivedMsg = myAgent.receive( MessageTemplate.MatchPerformative(ACLMessage.CFP)); (3) if (receivedMsg != null) { (4) order = (Object[]) receivedMsg.getContentObject(); (5) String productItem = (String) order[0]; (6) String productQuantity = (String) order[1]; (7) Object[] proposal = ((PlanForSuppliers) myPlan).makeAProposal(productItem, productQuantity, contextualCurrency);... (8) sendObjMsg(ACLMessage.PROPOSE, proposal, myAgent, receivedMsg.getSender()); (9)... }

8. August 17, 2007 8/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM An Approach for Dynamic Contextual Regulation Information Provision in Open MASs It is based on: –A Top-Down Classification of Contextual Norms Environment Norms Organization Norms Role Norms Interaction Norms –A Contextual Normative Ontology –An Inference Rule Engine to Automatically Compose Related Contextual Norms Environment Norms Organization Norms Role Norms Interaction Norms LEGEND - Boundaries of:

9. August 17, 2007 9/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM at Work A Motivating Scenario: –An American customer wants to built a computer; –He sends a call for proposal (CFP) to suppliers; –Suppliers answer the CFP with their proposed prices; –The American customer chooses a proposal and informs his decision to the chosen supplier. OrganizationCountryState PintelUSAMissouri IMDUSAVirginia BasusJapanOsaka BasusUSAUSACalifornia MacrostarChinaShanghai MacrostarJapanJapanHiroshima DescriptionBase price (in USD)Supplier Pintel CPU1500Pintel IMD CPU1200IMD Pintel Motherboard250Macrostar IMD Motherboard300Basus Memory 2 GB100Macrostar Memory 2 GB200Basus Hard disk 500 GB300Macrostar Hard disk 500 GB400Basus

10. August 17, 2007 10/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Top-Down Classification of Contextual Norms – Environment Norms Environment Norm for Payments: In all countries, negotiations are obliged to be paid in their national currency. Negotiations outside a country are obliged to have their values converted from its national currency to the national currency of the country where the seller is. Contextual Environment Norms for Payments: –In USA, all negotiations are obliged to be paid in American dollars (USD); –In Japan, all negotiations are obliged to be paid in Yen; –In China, all negotiations are obliged to be paid in Chinese yuan (CNY).

11. August 17, 2007 11/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Top-Down Classification of Contextual Norms – Environment Norms Environment Norm for Calculating Prices: In North America, a finished good from every organization is obliged to have its price increased by a fixed percentage (dependent of the seller location) as taxes, for immediate delivery or if the deliver address is in North America. Contextual Environment Norms for Calculating Prices: –In California, a state corporate income tax rate of 8.84 is obliged to be imposed on all sales; –In Virginia, a state corporate income tax rate of 6.00 is obliged to be imposed on all sales;

12. August 17, 2007 12/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Top-Down Classification of Contextual Norms – Organization Norms Organization Norm for Providing Warranty: Organizations are obliged to give a limited lifetime warranty. Contextual Organization Norms for Providing Warranty: –Basus organizations are obliged to give one year limited lifetime warranty; –Macrostar organizations are obliged to give six months limited lifetime warranty; –MacrostarJapan organizations are permitted to make an offer of two years limited lifetime warranty if a plus tax of 5% is accepted to be paid.

13. August 17, 2007 13/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Top-Down Classification of Contextual Norms – Role Norms Role Norm for Providing Discounts: Suppliers are permitted to give up to a limited percentage of discounts. Contextual Role Norms for Providing Discounts: –Pintel suppliers are permitted to give up to 5% discount; –IMD suppliers are permitted to give up to 8% discount on orders paid in cash.

14. August 17, 2007 14/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Top-Down Classification of Contextual Norms – Interaction Norms Interaction Norm for Providing Discounts: Suppliers are permitted to give up to a limited percentage of discounts if their products are bought in bundles. Contextual Interaction Norms for Providing Discounts: –IMD and BasusUSA suppliers are permitted to offer 15% discount if their products are bought in bundles.

15. August 17, 2007 15/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Top-Down Classification of Contextual Norms – Politic / Economic Norms Politic Norm for Operating in the Market: When USA and Japan are under political crisis, American organizations are prohibited to deal with Japanese organizations. Contextual Politic Norm for Operating in the Market –Mintor organizations are permitted to increase 10% of their prices when Watergate organizations are not operating in the American market. Economic Norms for Operating in the Market: An organization is obliged to make price fixing for, at least, six months when its competing organizations are not operating in the market. Contextual Economic Norm for Operating in the Market –Pintel organizations are obliged to make price fixing for six months when IMD organizations are not operating in the market.

16. August 17, 2007 16/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Contextual Normative Ontology

17. August 17, 2007 17/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Contextual Normative Ontology

18. August 17, 2007 18/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Contextual Normative Ontology

19. August 17, 2007 19/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Inference Rule Engine (1) Rule1- [ruleForEnvWithOEnvNorms: (2) hasNorm(?Env,?OEnvNorms) (3) <- hasNorm(?OEnv,?OEnvNorms), (4) belongsTo(?Env,?OEnv)] (5) Rule2- [ruleForOrgWithMOrgNorms: (6) hasNorm(?Org,?MOrgNorms) (7) <- hasNorm(?MOrg,?MOrgNorms), (8) hasMainOrganization(?Org,?MOrg)] (9) Rule3- [ruleForOrgWithEnvNorms: (10) hasNorm(?Org,?OrgEnvNorms) (11) <- hasNorm(?OrgEnv,?OrgEnvNorms), (12) isIn(?Org,?OrgEnv)] (13) Rule4- [ruleForRoleWithOrgNorms: (14) hasNorm(?Role,?OrgNorms) (15) <- hasNorm(?Org,?OrgNorms), (16) isPlayedIn(?Role,?Org)]

20. August 17, 2007 20/28 Carolina Howard Felicíssimo © LES/PUC-Rio DynaCROM – Reasoning in a DynaCROM MAS Purchase Criteria: Minimize Costs –Buy the bundle IMD/BasusUSA In IMD: 1,200.00 (IMD CPU) + 300.00 (IMD Motherboard) + 200.00 (Memory) + 400.00 (Hard Disk) = 2,100.00 – 15% (IMD/BasusUSA bundle discount) = 1,785.00 + 6% (Virginia’s corporate income tax). –In BasusUSA, then, the corporate income tax of 8.84% from California should be applied instead of the 6% from Virginia Purchase Criteria: Maximize the Warranty Period –Buy in MacrostarJapan for getting two years limited lifetime warranty. However, there, orders should be paid in Yen. –If he decides to buy in Pintel, suppliers can give 5% discount and the corporate income tax of 6.25% from Missouri should be applied. (1,500.00 (Pintel CPU) – 5% (Pintel suppliers’ discount) + 6,25% (Missouri’s corporate income tax)) + 250.00 (Pintel Motherboard) + 100.00 (Memory) + 300.00 (Hard Disk) + 32.50 (plus tax for extending warranty).

21. August 17, 2007 21/28 Carolina Howard Felicíssimo © LES/PUC-Rio Enforcing DynaCROM Contextual Norms Agent Contexts abcd abcdabcd abcd obligation Contextual Norms Agent Actions abcd abcdabcd abcd obligation Agent Contextual Norms Agent Contexts Norm Enforcement MOSES / SCAAR Agent Contextual Norms abcd abcdabcd abcd abcd abcdabcd DynaCROM

22. August 17, 2007 22/28 Carolina Howard Felicíssimo © LES/PUC-Rio Enforcing DynaCROM Contextual Norms With LGI public void sent(…) { if (message.startsWith("CFP")) { … doForward(); return; } 1 public void arrived(…) { if (message.startsWith("CFP")) { doAdd(“manufacturerCurrency(" + getMessageContent(message) + ")"); … doDeliver(); return; } CFP(currency,USD) ACalifornianManufacturer AMacrostarSupplier AMacrostarSupplierPolice CFP(currency,USD) ACalifornianManufacturerPolice 2 1 2 3 5 3 4 CFP(currency,USD) manufacturerCurrency = USD 4 5

23. August 17, 2007 23/28 Carolina Howard Felicíssimo © LES/PUC-Rio Enforcing DynaCROM Contextual Norms With LGI public void sent(…) { if (message.startsWith(“PROPOSE")) { doAdd(“currency(“ + getMessageContent(message) + ")"); doImposeObligation("checkCurrency", 1, "sec"); return; } ACalifornianManufacturer AMacrostarSupplier AMacrostarSupplierPolice currency = USD manufacturerCurrency = USD “Ok!” PROPOSE(USD,26157.5) public void arrived(…) { if (message.startsWith("PROPOSE")) { doDeliver(); return; } PROPOSE(USD,26157.5) ACalifornianManufacturerPolice 1 1 2 2 3 4 3 if (obligationTerm.equals("checkCurrency")) { … if (currency.equals(manufacturerCurrency) ) { doForward(); doDeliver(CS.toString(), "Ok!", sourceAddress); } else { doDeliver(CS.toString(), "NOk!", sourceAddress); } …} 3 4 5 5 6 6

24. August 17, 2007 24/28 Carolina Howard Felicíssimo © LES/PUC-Rio Enforcing DynaCROM Contextual Norms With SCAAR (1) SCAARNorm1- (2) [(agt: aGenericAgent) (3) OBLIGED (agt do PayWithNationalCurrency with environment.hasCurrency = "USD") (4) IF (agt be environment with environment = "USA") (5) OR IF (agt be environment with environment.belongsTo = "USA")] (6) SCAARNorm2- (7) [(agt: aMintorSupplierAgent) (8) OBLIGED (agt do GiveALimitedLifeTimeWarranty with organization.hasLimitedLifeTimeWarranty = "SixMonths") (9) IF (agt be organization with organization = "Mintor") (10) OR IF (agt be organization with organization.hasMainOrganization = "Mintor")]

25. August 17, 2007 25/28 Carolina Howard Felicíssimo © LES/PUC-Rio Related Work Important works concerning regulations in the domain of MASs have been proposed recently (e.g., OMNI, XMLaw,…). However, these solutions seem to lack the necessary flexibility and dynamics for norm evolution in open systems. The use of contexts permits a more precise mechanism to deal with norm evolution The use of ontologies and ontology-driven rules provides a reasonable dynamics for norm evolution, at system run- time, and also a meaningful way for heterogeneous agents to interpret precise contextual norm information in open MASs.

26. August 17, 2007 26/28 Carolina Howard Felicíssimo © LES/PUC-Rio Conclusion The motivating question of my research is how to easily implement regulation in open MASs permitting heterogeneous agents to perform efficiently and coherently. The thesis we held here is that the complexity of norm management in open MAS can be decreased by decoupling information in contexts. DynaCROM aims to be a straightforward method to smoothly apply and manage regulations in open MASs, enforcing customized compositions of contextual norms. The main goal of DynaCROM is not specifically the enforcement mechanism, but how to provide a dynamic solution for regulating open MASs.

27. August 17, 2007 27/28 Carolina Howard Felicíssimo © LES/PUC-Rio Conclusion DynaCROM is still a work in progress, but we agree that it already has important contributions for the domain of regulation in open MASs. Its main contributions are: –Definition of a top-down classification for contextual norms which facilitates the tasks of elucidation, organization and management of norm information; –Definition of a contextual normative ontology to explicitly represent the semantic of classified norms in a meaningful way (i.e., with a common understanding) for heterogeneous agents; –Definition of a norm composition process, based on ontology-driven rules, that permits easily update in the system regulation by evolving norms in a unique resource (an ontology) and/or by activating rules for different customized compositions of contextual norms; –A solution for enforcing contextual norms

28. Questions ?