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Web Services. By Joshua Moorehead Jayme Bennett. What are Web Services?. Client and server applications The client uses an application to make a request to a server application Method of communications This allows users to access requested data without it being stored in-house.
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Web Services By Joshua Moorehead Jayme Bennett
What are Web Services? • Client and server applications • The client uses an application to make a request to a server application • Method of communications • This allows users to access requested data without it being stored in-house
Web Services(application services) • Combination of programming and data • Application Components • Easily Accessible • Self-contained and Self-describing
Two types of uses • Reusable application components • Some applications need specific data that is used multiple times. Reusing code to fit a particular service saves on development • Connect existing software • Linking existing data helps to improve problems dealing with interoperability
Categories of Web Services • Business Information • Sharing information with consumers or other businesses • Business Integration • Travelocity, eBay, CreditKarma • Business Process Externalization • Extremely useful to integrate processes • Adds value for Global business processes
Implementation • Web services can implement a service-oriented architecture • Service-Oriented Architecture(SOA) • Software that provides an application functionality as services to other applications
Service-Oriented Architecture • Benefits • Data exchange is easy and simultaneous • Reusable • Low development and maintenance costs • Organizational Benefits • Agility • Cost Reductions • Return on Investment
IT Benefits • Meeting IT Goals • Simpler systems • Lowering maintenance costs • Enhancing architectural flexibility • Lowering integration costs
Service-Oriented Architecture • Interoperability • Common payload and protocol • Published and discoverable interfaces • Loose coupling • Multiple communication interfaces • Composability
Service Architecture • Physical Design • Databases, software, legacy systems, XML schemas, data stores
Entities of SOA • Service Providers • Creates the Web Service Interface • Publishes interface to service registry • Service Consumers • Web Service client retrieves data from the broker’s registry • Service Directories/Brokers • Returns information about how to bind a service
How do Web Services use SOA? • SOA is the overall software application • A blueprint • IT strategy • Web Services • Standard communication mechanisms • Constructed chunks and components
Web Services Standards • There are four different types of Web Service Standards. • WSDL (Web Services Description Language) • SOAP (Simple Object Access Protocol) • REST (Representational State Transfer) • UDDI (Universal Description Discovery and integration.)
What is WSDL? • XML based interface description language used to describe the functionality of the web service. • Often combined with SOAP and an XML schema to provide web services over the internet. • Developed by IBM, Microsoft and Ariba to describe web services for their SOAP toolkit.
Web Service Addressing • URI (Uniform Resource Identifier • http://live.capescience.com/ccx/GlobalWeather • Only used by programs and not by humans.
SOAP • It is a protocol specification for exchanging structured information • Basic messaging framework upon which web services can be built • Consists of three parts • An envelope, defines what is in the message and how to process it • A set of encoding rules for expressing instances of application data types • A convention for representing procedure calls and responses
Parts of SOAP • Consists of three parts. • An envelope, defines what is in the message and how to process it. • A set of encoding rules for expressing instances of application data types. • A convention for representing procedure calls and responses.
SOAP continued • Has 3 major characteristics. • Extensibility • Neutrality • Independence
How can SOAP be used? • Can be used to talk to a real-estate database to transmit data.
Pros and Cons • Advantages • SOAP is versatile enough to allow for different transport protocols. • Works will with firewalls. • Disadvantages • Can be slower than some competing middleware technologies such as COBRA or ICE. • When using http, only one party(the client) can use the services of the other.
RESTful Web Services • REST – Representational State Transfer • An alternative to SOAP • While SOAP focuses on standard communication protocols REST describes a set of architectural principles. • Stateless operations • Manipulates existing state of resources through XML
About REST • Completely Stateless • Good caching infrastructure • No standard set of rules • Useful for restricted-profiles • Easy to integrate • Simple compared to SOAP
UDDI • Platform-independent, XML based registry to locate web service applications. • Originally intended as a core web service standard. • Designed to be interrogated by SOAP messages and to provide access to WSDL documents describing the protocol bindings and message formats.
UDDI Structure • White Pages • Address, contact, and known identifiers. • Yellow Pages • Industrial categorization based on standard taxonomies • Green Pages • Technical information about services exposed by the business.
White Pages • Gives Information about the business supplying the service. • Includes name of business and a description of the business • Contact information for business is also provided.
Yellow Pages • Provides a classification of the service or business. • Because a business may provide a number or service, there may be several yellow pages associated with on ewhite page.
Green Pages • Gives information on how to access a web service, with information on service bindings. • Gives the address of the service and the parameters and references to specification of the interfaces
History of UDDI • Written in 2000 • Writers had a vision that that consumers of web services would be linked up with providers through a public brokerage system. • UDDI didn’t catch on as planned
Web Services Protocol Stack • Service Transport • XML Messaging • Service Description • Service Discovery
Security Issues • Web Services are program-to-program not human-to-program interactions • XML • Digital Signature • Encryption • Key Management Specification • SAML (Secure Assertion Markup Language) • XML-based framework
Who uses Web services? • eBay • Extending APIs that make its site a platform • Amazon.com • Amazon Web Services(AWS) • Collection of Web Services
Amazon Web Services • Launched in 2006, first year 180,00 developers signed up. • Accessed over HTTP using REST and SOAP Protocols. • Most popular web services are Amazon EC2 and Amazon S3.
Netflix and Amazon • Netflix and Amazon Prime are competitors in the streaming media services market. • Netflix uses Amazon AWS for several functions. • Using amazon AWS Netflix has grown exponentially because of the reliability of AWS.
New Development in Web Services • Web API • Development in webservices making it simpler. • Simpler also means cheaper. • There are many critics of non-RESTFUL web services.
Oracle • Oracle • Oracle Web Services manager(OSWM) • Two categories of Web Services in Oracle • Weblogic Web Services • Oracle Infrastructure Web Services • Other Oracle Web Services products • Oracle Jdeveloper • Oracle Enterprise Manager Fusion Middleware Control • WebLogic Server Scripting Tool
SAP • SAP is a leading develop of web services. • Tools for Web Service Development • SAP Web Application Server • SAP NetWeaver Developer Studio
The future of Web Services • Web 2.0 • Web Services and Cloud Computing