DAML-S: Semantic Markup for Web Services DAML-S Web Services Coalition presented by: Terry R. Payne Carnergie Mellon University

DAML-S Web Services Coalition CMU: Anupriya, Ankolekar, Massimo Paolucci, Terry Payne, Katia Sycara BBN: Mark Burstein Nokia: Ora Lassila Stanford KSL: Sheila McIlraith, Honglei Zeng SRI: Jerry Hobbs, David Martin, Srini Narayanan [Yale: Drew McDermott & Manchester: Ian Horrocks] Slides courtesy of Sheila McIlraith, Stanford KSL

What is DAML-S? DAML-S: A DARPA Agent Markup Language for Services DAML+OIL Ontology for (Web) services AI-inspired markup language: tailored to the representational needs of Services expressive power well-defined semantics ontologies support reuse, mapping, succinct markup,... Release of DAML-S version 0.5 June,2001

Layered Approach to Language Development The first major application of DAML+OIL Layer exists above DAML+OIL Future versions will build upon emerging layers (e.g. DAML-Rules etc) DAML-S (Services) XML (Extensible Markup Language) RDF (Resource Description Framework) RDFS (RDF Schema) DAML+OIL (Ontology)

DAML-S Objectives Provide: an upper ontology for describing properties & capabilities of agents & (Web) services in an unambiguous, computer interpretable markup language. Desiderata: an ontology of Web services ease of expressiveness enables automation of service use by agents enables reasoning about service properties and capabilities

Automation Enabled by DAML-S Web service discovery Find me a shipping service that transports goods to Dubai. Web service invocation Buy me 500 lbs. powdered milk from Web service selection, composition and interoperation Arrange food for 500 people for 2 weeks in Dubai. Web service execution monitoring Has the powdered milk been ordered and paid for yet?

Upper Ontology of Services

Presenting Service Profiles Service Profile Presented by a service. Represents “what the service provides” One can derive:  Service Advertisements  Service Requests DAML-S:

DAML-S Service Profile (Overview) High-level description of a service and its provider description of service (human readable) specification of functionalities service provides functional attributes (requirements and capabilities) Profile used for populating service registries automated service discovery matchmaking

DAML-S Service Profile (Overview) Provenance Description Functional Attributes Functionality Description

DAML-S Service Profile Provenance Description Information and Provenance about the Service serviceName & textDescription intendedPurpose & role of 3 rd Party Actors Details about 3 rd Party Actors Requesters Providers

DAML-S Service Profile Functionality Description Specification of what the service provides High-level functional representation in terms of:  preconditions  accessConditions  inputs  outputs  conditionalOutputs  effects Summarizes the top-level Composite Process (described by Service Model)

DAML-S Service Profile Functional Attributes geographical scope Pizza Delivery only within the Pittsburgh area quality descriptions and guarantees Stock quotes delivered within 10 secs service types, service categories Commercial / Problem Solving etc service parameters Average Response time is currently... Provide supporting information about the service, including:

Upper Ontology of Services

Describing Service Models Service Process Describes how a service works. Facilitates (automated) Web service invocation composition interoperation monitoring DAML-S:

DAML-S Service Model (Overview) Service Model may be used to 1) to perform a more in-depth analysis of whether the service meets its needs; 2) to compose service descriptions from multiple services to perform a specific task; 3) during the course of the service enactment, to coordinate the activities of the different participants; 4) to monitor the execution of the service. For non-trivial services, the first two tasks require a model of action and process, the last two involve, in addition, an execution model.

DAML-S Service Model (Overview)

DAML-S Service Model “How does it work?” Each service is conceived as simple or composite process (event/action) Associated with each service is a set of inputs, outputs, preconditions and effects (function and action metaphor) Composite processes are compositions of simple or other composite processes in terms of constructs such as sequence, if-then-else, fork,... Data flow and Control flow should be described for each composite service A black box and glass box view are given of each composite service

Function/Dataflow Metaphor Acme Book Truck Shipment Acme Book Truck Shipment Input: confirmation #... Output: failure notification … truck available + valid credit card Y N ? customer name origin destination weight pickup date...

AI-inspired Action/Process Metaphor Input: confirmation #... Output: failure notification … truck available + valid credit card Y N ? Preconditions: customer name origin destination pickup date... knowledge of the input... goods at location if successful credit card debited... Effect: Output: Effect: Acme Book Truck Shipment Acme Book Truck Shipment

AcmeTruckShipping book flight service customer name flight numbers dates credit card no.... confirmation no.... failure notification errror information … ? book hotel service confirmation no. dates room type credit card no.... confirmation no.... failure notification … ? book car service customer name location car type dates credit card no.... confirmation no.... failure notification … ? Composite Process ? Input & Preconditions Input & Preconditions Output & Effects Output & Effects

Composite Process (cont) Acme Truck Shipping Service Acme Truck Shipping Service expands AcmeTruckShippingExpandedAcmeTruckShipping truck available + valid credit card Y N Confirm Shipping Region Get Quote Get Shipping Dates Book Truck Shipment

AcmeTruckShipping ExpAcmeTruckShipping expand Composite Process (cont)

Upper Ontology of Services

Supporting a Service Grounding Service Process Provides a specification of service access information. Specifies: communication protocols, transport mechanisms, etc. E.g., SOAP, HTTP forms, KQML, OAA ACL, Java RMI, RPC, etc. DAML-S: Under Construction …

Upper Ontology of Services Review:

Related Work Related Industrial Initiatives These XML-based initiatives are currently complementary to DAML-S. DAML-S intends to build on top of these efforts exploiting increased expressiveness, semantics, inference that enables automation. Related Academics Efforts Process Algebras (e.g., Pi Calculus) Process Specification Language (Hoare Logic, PSL) Planning Domain Definition Language (PDDL) Business Process Modeling (e.g., BMPL) Service Description Languages (e.g., LARKS) UDDIebXML WSDL(dot).NET XLANGBizTalk, e-speak etc

Exploiting Ontologies of Services Service Shipping BuyBook AmazonBuyBook CongoBuyBook BuyTicket BuyAirTicket Purchase AirShipping TruckShipping BoatShipping AcmeTruckShipping BuyConcertTicket DAML-S:

Tools and Applications DAML-S provides a means of describing Web services. It’s just another DAML+OIL ontology  all the tools and technologies that exist for DAML+OIL are relevant Some DAML-S Specific Tools and Technologies: Extending DAML-S: DAML-S Coalition (security, symbol grounding, …) Discovery, Matchmaking, Agent Brokering: CMU, SRI (OAA), Stanford KSL Automated Web Service Composition: Stanford KSL, BBN/Yale/Kestrel, CMU, MIT, Nokia, SRI DAML-S Editor: Stanford KSL, SRI, CMU (profiles), Manchester Process Modeling Tools & Reasoning: SRI, Stanford KSL Service Enactment /Simulation: SRI, Stanford KSL

Challenges Technical Issues DAML+OIL not sufficient for the process model Laundry list of unaddressed & resolved issues (SRI & CMU will mention some this afternoon) (some will be mentioned in Breakout tomorrow) Connecting with Industry Initiatives & with User Community need to connect DAML-S with industry initiatives need people in industry (& in DAML) to mark up services with DAML-S concern: industry’s lack of adoption of RDF Tools availability DAML+OIL reasoner DAML-S editor

Challenges Technical Issues DAML+OIL not sufficient for the process model Laundry list of unaddressed & resolved issues messages, synchronization, conversation protocols, exceptions and transaction, multiple participants, scripts, unification/binding, constraints, ontologies of processes, service grounding,... Connecting with Industry Initiatives & with User Community need to connect DAML-S with industry initiatives need people in industry (& in DAML) to mark up services with DAML-S concern: industry’s lack of adoption of RDF Tools availability DAML+OIL reasoner DAML-S editor

Challenges Technical Issues DAML+OIL not sufficient for the process model Laundry list of unaddressed & resolved issues (SRI & CMU will mention some this afternoon) (some will be mentioned in Breakout tomorrow) Connecting with Industry Initiatives & with User Community need to connect DAML-S with industry initiatives need people in industry (& in DAML) to mark up services with DAML-S concern: industry’s lack of adoption of RDF Tools availability DAML+OIL reasoner DAML-S editor

Status: DAML-S version 0.5 released June, Please get involved!  Break-out Session (Friday)  *** Try DAML-S for your application *** give feedback ***  DAML-S version 0.5 and related papers  mailing list (technical discussions) (announcements) We Want Your Input!

Acknowledgements Slides created by Sheila McIlraith, KSL Stanford Ontology images created by Terry Payne, CMU

Who Will Use DAML-S? Web service providers (e.g., Amazon, Intelink, United Airlines)  mark up their services 3rd party Web page designers (e.g., Web Designers)  mark up clients’ services 2nd-ary Web service providers (e.g., Travelocity, My Simon)  exploit others’ services to create add-on services  use/write agent software to find/execute/compose other services Web service end users (e.g., Joe, Analysts)  characterize their needs  use/write agent software to find/execute/compose services