1 Web Service Integration Michael R. Genesereth Logic Group Stanford University

2 World Wide Web

3 Changing Landscape WWW began as a distributed document management system HTML pages Multimedia Links WWW becoming a medium for distributing services as well Databases Transformational software Buying and selling goods, services, equities, etc. Shipping goods Booking travel

4 FX-Agents Project Mission: to produce technology that promotes web services * Automated Service Discovery finding services among vast and changing set of possibilities * Automated Service Composition e.g. planning a trip, buying a car online, etc. especially useful for one-off tasks * Incremental Service Creation e.g. supply chain mgmt, enterprise mgmt, portfolio mgmt new services for personal, corporate, or public use especially useful for ongoing tasks

5 Service Network

6 Integrated Service Architecture Result Facilitator Request QBF (Query by Form) - User queries Internet in his own schema ABF (Application by Form) - User requests services using own schema Insurer 1 Insurer 2 Appraiser Title Company Bank 1 Bank 2 Bank 3

7 Declarative Programming What Versus How Users and programmers provide declarative info (what) System uses declarative info to determine behavior (how) (Such systems are sometimes called intelligent agents) Types of Information (expressed in logical languages) Model of environment and explicit statement of goals Specifications of services Behavioral constraints - laws, contracts, business rules, etc Declarative information explicit and task independent Ease of programming Ease of maintenance Runtime Flexibility

8 Sample Service Specifications If p requests a mortage from WFB for x dollars for house h and c appraises h for y dollars and c is approved and y≥x and there is insurance on house h for z dollars and z≥x, Then WFB will loan p x dollars secured by h. If p requests an appraisal for house h from Jones Then Jones will appraise h for x dollars. If p requests insurance from Allstate for x dollars on house h and c appraises h for y dollars and c is approved and y≥x, Then Allstate will insure h for x dollars.

9 Service Discovery Example If p requests insurance from Allstate for x dollars on house h and c appraises h for y dollars and c is approved and y≥x, Then Allstate will insure h for x dollars. Request: Find a company c such that c will insure Myhouse for $1,000,000. Answer: Allstate will insure Myhouse for $1,000,000 dollars provided that MRG requests from Allstate for $1,000,000 on Myhouse c appraises Myhouse for y dollars c is approved y≥$1,000,000

10 Service Composition Example Goal c will loan MRG 1,000,000 dollars secured by Myhouse. Specifications as before Plan (1) MRG requests an appraisal for house Myhouse from Jones. (2) MRG requests insurance from Allstate for 1,000,000 dollars on house Myhouse. (3) MRG requests a mortage from WFB for $1,000,000 dollars for house Myhouse.

11 Incremental Service Creation Rules

12 Service Creation Example If the apr of my mortgage rate is x and c will refinance my mortgage for y and x-y>0.25, Then find a new mortgage. If supply of paper runs below 50% and there is a supplier at or below standard price Then place order for 50% additional supply. If employee requests travel and the employee is a research scientist or above and the destination is a research conference and the projected cost is less than $2000 Then approve the request.

13 Global Trading Web Catalog Comprehensive catalog of products and services available from companies doing business on the Internet Info from catalogs, directories, inventories, ratings, etc Changes automatically propagated to subscribers Taxonomic, Parametric, Cross-category, Associative search Heterogeneity in schemas of suppliers and consumers Logic is used to codify relationships among these schemas Automated reasoning for query planning and optimization CS, Commerce One, CommerceNet, UCCNet (bar codes)

14 Regnet Integrated regulatory infrastructure through which individuals, companies, programs can find applicable rules and regulations can get help complying with those rules and regulations Application to electronic commerce on the Internet contracts, business rules, governmental regulations Computer Representation of contracts, rules, regulations Search, use Monitoring, Enforcement Analysis, Synthesis Computer Science, Civil Engineering, Law School

15 Summary Mission - technology for web services Service discovery Service composition Service creation Declarative Programming Technology Humans write definitions, constraints, specifications, rules Computer operationalizes that declarative information Ease of programming, ease of maintenance, flexibility Applications Project Management Enterprise Management Supply Chain management Portfolio Management

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