May 6, 2004 1
Service agents Publish “white page” services description
content and register the services at a “yellow page” site
Understand ontology and answer queries Link with the semantic web server and push
information to other agents
May 6, 2004 2
Features Distributed: no centralized agent who has to search all web
pages and understand every ontology The best agent to ask questions can be easily located: a
good amendment to the web services discovery and the agent services searching
The non-semantic web site joins the semantic world by linking to a service agent
The non-agent program can be wrapped with a service agent shell
Trustworthy: Owned by the semantic web site
May 6, 2004 3
Function Level I. Provide the requested semantic web page
II. Answers simple questions about the semantic web pages: The inference in this level is based on local rules, limited semantic pages and local ontologies
III. Answer complicated questions about the semantic web pages: The inference in this level involves multiple ontologies, multiple semantic web sites and multiple agents
IV. Validates trust and delegation
May 6, 2004 4
OWL as a Semantic Language Well-defined model-theoretic semantics Unambiguously computer-interpretable Facilitates a higher-level of interoperability
between the agents
By agreeing on how meaning is conveyed, applications can share meaningful content easily and naturally
May 6, 2004 5
OWL as ACL Content Language
I. OWL’s expressive power is adequate for many needs of current agent based systems
II. OWL offers better support for using terms drawn from multiple namespaces and multiple ontologies than existing ACL content languages
III. OWL provides improved support in modeling, maintaining and sharing ontologies
IV. OWL is designed to fit into and integrate with web-based information and web services
V. OWL has the potential to be a widely accepted and used representation language, enhancing the potential for interoperability among many systems
May 6, 2004 6
Semantic Web in FIPA FIPA is the most widely used MAS framework
Well developed and documents standards Good open source software
RDF is one of FIPA’s standard content languages OWL is widely used for publishing ontologies
within the FIPA community, for example, agentcities and openNet
May 6, 2004 7
FIPA Standards Overview
EnvelopeEncodingScheme
ACLEncodingScheme
CLEncodingScheme
TransportProtocol
InteractionProtocol
Envelope1 11 isTransmittedOver
Ontology
Message1
ACL
1
isExpressedIn1..*
1
1..*
1
contains
ContentLanguage
Symbol11..* 11..*
belongsTo
Content
1
1
1
1
contains
11 11
isExpressedIn
0..*
1
0..*
1
contains
1
IIOPHTTP
ACL
SL
fipa-agent-management
IDLXMLbit-eff
StringXMLbit-eff
String
request, query, request-whencontract-net, iterated-contract-netbrokering, recruitingsubscribe, propose
Owl as a content languag
e
Owl for ontologies
Owl for publishin
g protocols
Owl for publishing
communicative acts
--Tim Finin 2003
May 6, 2004 8
FIPA Agent Platform
AMS DF ACC
internal platform message transport
AAsoftware
IIOP
Agents belong to one or more agent platforms which provide basic services.
Owl for service
descriptions
Owl for authorization policies
Owl for representation and reasoning
Owl for user models and
profiles
--Tim Finin 2003
May 6, 2004 9
Outline
Part 1: Thesis and Contribution
Part 2: Background
Part 3: Research Question
Part 4: Agent-Based Services
Part 5: TAGA and F-OWL
Part 6: Conclusion
May 6, 2004 10
Why TAGA ? Need a big and complicated system to
evaluate the ideas Agentcities provides a robust global
agent services platform TAC is a successful travel market
simulation system
May 6, 2004 11
Trading Agent Competition The Trading Agent Competition
proposed (1999) and first run (2000) by Michael Wellman and Peter Wurman
Goal: promote and encourage research in markets involving autonomous trading agents;
Methods: trading agents operate within a travel market scenario;
International competitions in 2000, 2001 and 2002 were based on a simple travel scenario
May 6, 2004 12
Problems TAC classic assumes that agents interact via a
few centralized markets. Technology is basically client-server with well
defined APIs and simple XML encoding. Real word interactions are varied and rich
Customers can chose to interact with travel agencies, dynamic markets, or directly with service providers
Choices are governed by value, speed, reputation Rich information exchange abounds -- customers have
complex interests and preferences, service providers have detailed descriptions, etc.
Common ontologies are important Trust and reputations are important.
May 6, 2004 13
TAGA Features• Open Market Framework• Auction Services• OWL Message Content• Travel Market Ontology• Global Agent Community
• Goal: test bed for experimenting with Agents, Semantic Web and Web Services
May 6, 2004 14
A Typical ScenarioA Typical Scenario
BulletinBoard
CA TA
AuctionService
Airline WSHotel WS
1 2a
3
4
5
6
2b
Market Oversight Agent
May 6, 2004 15
TAGA Agents (1)……..
Customer Agents
One CA joins the Game every 30 Sec.
Hotel Web Service
EntertainmentWeb Service
Airline Web Service
TA-1 (AAP)
TA-2 (AAP)
TA-4 (JADE)
Find travel arrangements Save $$
Organize travel Maximize profits
sell “goods” Maximize profits
May 6, 2004 16
TAGA Agents (2)
Market OversightAgent
Auction Service Agent
Helps CA find one or more TA
Operates the auctions markets: English, Dutch, Priceline and Hotwire.
Manage the financial records
Announces the winning TA
Bulletin Board Agent
May 6, 2004 17
Dynamic Contract Protocol
May 6, 2004 18
Priceline Auction Protocol
May 6, 2004 19
Technology System Infrastructure:
Agentcities + AAP + JADE Travel and Auction Ontologies: OWL Web Services: WSDL Web technology:
Apache, MySQL Java Web Start
Agent Communication: FIPA (OWL as the content language) Service registration: OWL-S
May 6, 2004 20
Simulation Design Game running continuously Travel Agent
Direct Buy or Bid Acquire resource before or after win customer Penalty, reputation
Auction Service Agent English & Dutch auction “Name your price” auction (priceline.com &
hotwire.com)
Travel Agent Game in Agentcities
http://taga.umbc.edu/
TechnologiesTechnologiesFIPA (JADE, April Agent Platform)
Semantic Web (RDF, OWL)
Web (SOAP,WSDL,DAML-S)
Internet (Java Web Start )
FeaturesFeaturesOpen Market FrameworkAuction ServicesOWL message contentOWL OntologiesGlobal Agent Community
MotivationMotivationMarket dynamicsAuction theory (TAC)Semantic webAgent collaboration (FIPA & Agentcities)
Travel Agents
Auction Service Agent
Customer Agent
Bulletin BoardAgent
Market Oversight Agent
Request
Direct Buy
Report Direct Buy Transactions
BidBid
CFP
Report Auction Transactions
Report Travel Package
Report Contract
Proposal
Web Service Agents
OntologiesOntologieshttp://taga.umbc.edu/ontologies/
travel.owl – travel concepts
fipaowl.owl – FIPA content lang.
auction.owl – auction services
tagaql.owl – query language
FIPA platform infrastructure services, including directory facilitators enhanced to use OWL-S for service discovery
Owl for representation and reasoning
Owl for service
descriptions
Owl for negotiatio
n
Owl as a content languag
e
Owl for publishing
communicative acts
Owl for contract
enforcement
Owl for modeling trust
May 6, 2004 22
ACL Content Statements: the price of this hotel in day 3 is
$100/night; Requests: create an airline auction instance; Contracts: if the Travel Agent TA1
successful organized the travel package, customer Joe will pay $400 to TA1, else, TA1 pay $200 compensation to Joe.
Policies: to win the contract of the customer Joe, the travel agent must have reputation better than average
May 6, 2004 23
Ontologies ACL
http://taga.umbc.edu/ontologies/fipaowl.owl Auction
http://taga.umbc.edu/ontologies/auction.owl Travel
http://taga.umbc.edu/ontologies/travel.owl
Submitted to DAML ontology library
May 6, 2004 24
Multiple Ontologies Support NewInstance OntologyQuery OntologyShare OntologyRelation
Agent A
Agent B
NewInstance
Agent A
Agent B
Agent B
Agent A
OntologyShare
OntologyQuery
OntologyQuery
OntologyRelation
May 6, 2004 25
TAGA in ActionTAGA in ActionTAGE Home Pagehttp://taga.umbc.edu
TAGA on Agentcities network(UMBCTac.agentcities.net)Baltimore, MD USAhttp://www.agentcities.net/
Download the latest TAGA pkg and docshttp://taga.umbc.edu/taga/download/
Create a TAGA game online
TAGA supports heterogeneous agent platform.A FIPA-JADE agent can interact with a FIPA-AAP agent
May 6, 2004 26
Conclusion (1)Conclusion (1) A rich framework for exploring agent-based
approaches to e-commerce applications. Auction services are developed to enrich the
Agentcities environment The use of Semantic Web languages (OWL)
improves agent interoperability OWL-S is employed to support agent service
registration, discovery and invocation A sourceforge project
May 6, 2004 27
Conclusion (2)Conclusion (2) Won the Best Student Entry in the
Agentcities sponsored Agent Technology Competition held at Barcelona in Feb. 2003
TAGA platforms have been running in Agentcity.Net for more than 16 months.
Invited to Intelligent System Demonstrations at IJCAI 2003 and AAMAS 2004
Used by people from US, Korea, Romania, etc.