What is a Web Service?

Distributed Computing ModelDistributed Computing Model Loosely Coupled, Course GrainedLoosely Coupled, Course Grained Standard HTTP TransportStandard HTTP Transport Sync/Async Programming ModelSync/Async Programming Model XML for TransportXML for Transport

Described by XML MetadataDescribed by XML Metadata Discovered via LookupDiscovered via Lookup

Web Services Advantages

Programming Language IndependentProgramming Language Independent Platform IndependentPlatform Independent Firewall FriendlyFirewall Friendly Sync RPC and Async messagingSync RPC and Async messaging Simple to implementSimple to implement

Web Services Stack

Common Internet Protocols (TCP/IP, HTTP, Common Internet Protocols (TCP/IP, HTTP, SMTP, FTP)SMTP, FTP)

Data Representation (XML)Data Representation (XML) Data Format Specification (XML Schema, DTD, Data Format Specification (XML Schema, DTD,

RDF, WDDX, XMLP)RDF, WDDX, XMLP) Web Services (SOAP, ebXML)Web Services (SOAP, ebXML) Service Description (WSDL)Service Description (WSDL) Service Discovery (UDDI)Service Discovery (UDDI) Service Integration/Workflow (WSFL?)Service Integration/Workflow (WSFL?)

Web Services Pack

TomcatTomcat JAX PACKJAX PACK

JAXP (Processing)JAXP (Processing) JAXB (Binding)JAXB (Binding) JAX-RPC (RPC)JAX-RPC (RPC) JAXM (Messaging)JAXM (Messaging) JAXR (Registry)JAXR (Registry)

JavaServer Faces (JSR-127)JavaServer Faces (JSR-127)

Other Java Initiatives

JSR 104 - XML Trust Services APIJSR 104 - XML Trust Services API JSR 105 - XML Digital Signature APIJSR 105 - XML Digital Signature API JSR 106 - XML Encryption APIJSR 106 - XML Encryption API JSR 109 - Implementing Enterprise Web JSR 109 - Implementing Enterprise Web

ServicesServices JSR 110 - JAVA APIs for WSDLJSR 110 - JAVA APIs for WSDL

Web Services Issues

SecuritySecurity AuthenticationAuthentication Business Process Flow (WFSL)Business Process Flow (WFSL) PerformancePerformance