2006 IEEE International Conference on Web Services ICWS 2006

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2006 IEEE International Conference on Web
Services ICWS 2006

• Overview

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Contents

• Introduction to Web Services
• SOA
• WS- Standrads
• Amazon Web Services
• Complex Events Processing

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Introduction to Web Services
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Web Services W3C Definition

• A Web service is a software system
• Identified by a URL, whose public interfaces and
  bindings are defined and described using XML
• Its definition can be discovered by other
  software systems
• These systems may then interact with the Web
  service
• using XML based messages conveyed by Internet
  protocols

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Web Services

• Web services are an emerging technology that
  offer a solution for providing a common
  collaborative architecture
• Web services provide functional building blocks
  which are not tied to any particular programming
  language or hardware platform
• They are accessible over standard Internet
  protocols

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The Evolution

• Online systems replace Batch systems
• Graphical User Interfaces replace green screens
• Networked systems replace standalone systems
• Internet based systems replace LAN based systems
• Future ???
• Web Services replace simple Internet and LAN
  based systems

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Web Services Technologies

• XML (eXtensible Markup Language)
• markup language that underlies most of the
  specifications used for Web services
• SOAP (Simple Object Access Protocol)
• (Simple Object Access Protocol), similar to JDBC,
  is a network, transport, and programming language
  and platform neutral protocol that allows a
  client to call a remote service. The message
  format is XML.
• WSDL (Web services description language)
• An XML-based interface and implementation
  description language. The service provider uses a
  WSDL document in order to specify the operations
  a Web service provides. 
• UDDI (universal description, discovery, and
  integration)
• Both a client-side API and a SOAP-based server
  implementation that can be used to store and
  retrieve information on service providers and Web
  services.

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How it works

• A Web Service is a URL-addressable software
  resource that performs functions (or a function)
• Web Services communicate using standard protocol
  known as SOAP (Simple Object Access Protocol)
• A Web Service is located by its listing in a
  Universal Discovery, Description and Integration
  (UDDI) directory

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Web Services Integration

• In a lot of organizations, the data and logic of
  one application are basically useless to other
  applications
• When an application and its data are isolated
  from other applications, we often say that they
  are in silos
• Web Services are better at sharing data and
  functions
• The result is that the silos come down, and
  previously isolated systems can talk to each other

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Web Services Access

• Web Services are especially good at providing
  access through different interfaces
• A Web Service can have a dedicated client
  application, but it can also be readily accessed
  through browsers, wireless devices,
  voice-activated interfaces, and so on
• Adding new access methods is much simpler than
  with a traditional application

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Web Services Flexibility

• One of the more important innovations in Web
  Services is machine-to-machine communications
• This means that a Web Service can ask another Web
  Service to do something, and that Web Service can
  ask another Web Service to do something, and so
  on
• In the future, many Web Services will really just
  be aggregations of other Web Services

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Web Services Application Assembly

• Future applications will be assembled from a
  diverse group of web services, aggregating
  functionality
• Reusability is extended to the execution level,
  versus reusability from just the design and
  construction level

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SOAP

• Simple Object Access Protocol
• SOAP is an open protocol specification defining a
  uniform way of performing RPCs using HTTP as the
  underlying communications protocol with XML for
  the data serialization.

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How Is a Service Described?

• WSDL (Web Service Description Language)
• XML-based
• W3C for standard

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How Do I Find Web Services?

• UDDI project by Microsoft, IBM, and others
• Take a look at uddi.org
• Websites
• //www.xmethods.net
• //www.salcentral.com

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XMethods
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Currency Exchange
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Using the Currency Exchange Web Service
Currency Exchange WS
RV Application
Internet
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Current Web Service Protocol Stack
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Adoption of Web Service Protocols