OWL-P: Protocols for Processes Toward the Pragmatic Web Munindar P. - PowerPoint PPT Presentation

OWL-P: Protocols for Processes Toward the Pragmatic Web Munindar P. Singh ( Students: Amit K. Chopra, Ashok U. Mallya) singh@ncsu.edu Department of Computer Science North Carolina State University http://www.csc.ncsu.edu/faculty/mpsingh/ DARPA DAML PI Meeting, May 2004 – p.1/17

Why Processes and Protocols? Heavy interest from IT practitioners. Standardization efforts. Match with Semantic Web research. Tractable problems with high impact. Great application area for semantics. Segue into upcoming research program. DARPA DAML PI Meeting, May 2004 – p.2/17

Emphases of this Project: 1 t n Dynamic e e c n Organizations m Not in 2004 n t o i c a t i l a a p n Rule-Based d i e l m Commitment a o d v c n Protocols a d d n n n a a o i Commitment t g g a n n t i i l Protocols r n e o e t d i m o n e o l M p Protocols M m I Not in 2004 DARPA DAML PI Meeting, May 2004 – p.3/17

Emphases of this Project: 2 Protocols: Support reuse via abstraction and composition for process modeling and enactment. Commitments: Enable flexible modeling and enactment of protocols. Engineering: Full automation is not needed. Tools needed for engineering. Modeling and validation. Implementation and enactment. Monitoring and compliance. DARPA DAML PI Meeting, May 2004 – p.4/17

Trends and Assessment Increasing # of business protocols. IOTP , Escrow, SET, NetBill, . . . RosettaNet: 107 Partner Interface Processes (PIPs). ebXML Business Process Specification Schema (BPSS). Generally highly limited: two party, request-response protocols. No commitments; no formal semantics. Limited support for modeling or enactment. DARPA DAML PI Meeting, May 2004 – p.5/17

Simple Scenario and Example Run A customer (C) looks up a book at a vendor (B) and is quoted price and availability. C orders the book from B. B ships to C. C pays B. s 0 reqQuote(c,b,g) s 1 sendQuote(b,c,g,p) s 2 sendAccept(c,b,p) s 3 sendGoods(b,c,g) s 4 sendMoney(c,b,p) s 5 Customer, c Bookstore, b DARPA DAML PI Meeting, May 2004 – p.6/17

Challenges: Modeling Refinement: pay by credit card versus pay. Extensibility: verify C’s attributes, e.g., age. Adjustment: receive payment before shipping; receive book before paying. Alternative execution examples: B arranges for a shipper (S) to deliver the book to C. C pays via bank (K). Compose a process from the above. DARPA DAML PI Meeting, May 2004 – p.7/17

Process View: Global or Protocol? Pay Bank Bookstore Send Select Customer Receipt Bookstore Customer Ship Customer Bookstore Customer Shipper Bookstore Bookstore Ship Select Order Shipper Pay Ship Customer Pay Bank DARPA DAML PI Meeting, May 2004 – p.8/17

Example Run: Pay via Bank s 0 s 1 reqQuote(c,b,g) s 2 sendQuote(b,c,g,p) sendAccept(c,b,p) s 3 s 21 s 4 sendGoods(b,c,g) authPay(c,b,p) sendMoney(k,b,p) s 5 Customer's Bookstore, b Customer, c Bank, k DARPA DAML PI Meeting, May 2004 – p.9/17

Example Run: Shipper Protocol reqQuote(m,s,[gv]) s 10 sendQuote(s,m,[gv],q) s 11 sendAccept(m,s,[gv],q) s 12 s 13 s 13 sendGoods(m,g,s) s 14 sendGoods(s,v,g) s 15 sendMoney(m,s,q) s 15 s 16 Receiver, v Sender, m Shipper, s DARPA DAML PI Meeting, May 2004 – p.10/17

Example Run: Composed Purchase reqQuote(c,b,g) s 0 sendQuote(b,c,g,p) s 1 sendAccept(c,b,g,p) s 2 Shipping reqQuote(b,x,[gc]) s 3 sendQuote(x,b,[gc], px) s 11 s 12 sendAccept(b,x,[gc],px) s 13 s 13 Payment sendGoods(b,g,x) s 14 authPay(x,p) sendGoods(x,c,g) s 4 sendMoney(b,x,px) sendMoney(k,x,p) s 21 s 5 s 16 Shipper, x Bank, k Customer, c Bookstore, b DARPA DAML PI Meeting, May 2004 – p.11/17

Challenges: Enactment Behaving adaptively: decide dynamically to ship before payment to trusted Cs. Handling exceptions . External problems: cannot ship book. Detecting violations: no payment; book arrives damaged. Correcting violations: remind, complain, refund, . . . Exploiting opportunities: combine orders from same C. DARPA DAML PI Meeting, May 2004 – p.12/17

Example Run: Return and Refund Example: Uniform Commercial Code (UCC) allows returns with refunds for goods that are received damaged. reqQuote(c,b,g) s 0 s 1 sendQuote(b,c,g,p) s 2 acceptQuote(c,b,p) s 3 sendGoods(b,c,g) s 4 sendMoney(c,b,p) s 5 s 5 returnGoods(c,b,g) s 18 s 19 sendRefund(b,c,p) Customer, c Bookstore, b DARPA DAML PI Meeting, May 2004 – p.13/17

Architecture Maintains protocol state: Ex: Business policies, Binds to roles, interacts Commitments and propositions, pricing policies with other roles. roles being played, ... Rule Base updates lnternal Policy Main consults Knowledge Base queries Protocol Rules Usually several roles per agent Agent Playing a Role Messages Rules dictated by protocols being enacted Local domain Public domain Roles Propositions Rules Usually several Commitments Messages protocols, each with multiple roles Protocol Specified in OWL-P DARPA DAML PI Meeting, May 2004 – p.14/17

Deliverables OWL-P: OWL for protocols. Roles. Messages: content as propositions and commitments. Rules to describe messages and role constraints. Autonomous communicating agents (JADE). Tool to generate skeletons from OWL-P . Rule-based policies that help agents satisfy their protocol roles. Methodology to develop agents. DARPA DAML PI Meeting, May 2004 – p.15/17

Functionality and IP Status Open source; on SemWebCentral 6/30 onwards. Preliminary versions implemented for OWL-P . Multiagent architecture to enact. Policy-based architecture for each agent. Upcoming versions. Incorporate rules better (6/30). Compose protocols (6/30). Fully treat commitments (9/30). Represent quality of service for configuration (9/30) and apply it (12/31). Incorporate policies (12/31). DARPA DAML PI Meeting, May 2004 – p.16/17

Papers on this Topic “Protocols for Processes: Programming in the Large for Open Systems.” OOPSLA , Oct 2004. “Agent Communication Languages: Rethinking the Principles.” IEEE Computer , 31(12):40–47, Dec 1998. “An Ontology for Commitments in Multiagent Systems.” AI & Law , 7:97–113, 1999. “Reasoning About Commitments in the Event Calculus: An Approach for Specifying and Executing Protocols.” Annals Math & AI , 42(1-3), 2004. “Verifying Compliance with Commitment Protocols.” J. Auton Agents & MAS , 2(3):217–236, Sep 1999. DARPA DAML PI Meeting, May 2004 – p.17/17