What are web services?
This presentation answers questions with an example to make it easy to understand for technical and non-technical readers. 4 Circles LLC is a company committed to educate its clients and general public on information technology and how they are used.
2. Overview As an example we consider Ashram Hotels, a five star hotel. Ashram Hotels has been in hospitality business for more than 20 years and has acquired many different application systems which work on different operating systems. Their goal is to facilitate data transfer between these systems and make data access seamless Confidential
3. Data Data exists in text files, excel sheets, databases and other propretiary formats. These need to be transferred between one system to another say Housekeeping and Reservation systems. Data access to the user should be seamless – that they need not log on to different systems to access information. Confidential
7. Delivery.com is a service where guests can order from nearby restaurants, laundry etc. e-Fax VOIP G-Maps Delivery.com Wireless
8. Access To access the various systems in previous slide employee and also guests (for some of the systems) need an interface (client interface). These can be a web page, an application, mobile device etc. The card key system also needs to de-activate when the guest checks out which is another client interface. Confidential
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10. Kiosks are available for check-In and other guest services.
13. Legacy methods of reservations and check-in and out will also be options for guests – like reception desk, TV and even Fax. Kiosks Room Key/Check In MS Surface iPhone Online Res. Wireless Devices eFax TV Res.
14. Issues There are different clients and systems which may not be compatible with some of the clients. With self-reservation on the rise Ashram hotels is behind the competition. Employees and guests need to refer to say Google Maps for directions rather than that being integrated. Reports to directors and executives takes many weeks to prepare. Confidential
15. Solution Integrating these various systems to the clients is the solution. The best solution is to utilize what systems in place and integrate them with the clients and between themselves. The method of integration is called middleware services and sometimes loosely called web services- as most of the data is transferred over the web via HTTP protocol. Confidential
17. Middleware Services Confidential Each system has different protocols to communicate with their middle-ware. Some use XML (a customized HTML) - a stream or a file is passed. Documents can also be passed between systems MS technology ‘s SOAP has recently gained a lot of popularity with Web Services . Web Services is the global method which includes receiving messages from all kinds of clients i.e. wireless devices and traditional systems. Middleware Services can be loosely defined as services which bring about communication between heterogeneous application systems. E.g. J2EE app with .NET app or any other proprietary applications. The middleware connects users /systems with other systems.
18. Between Systems Middleware Systems exist internally between say two or more systems which may have to be written. These integration APIs (Application Programming Interface) can be bought or written. WARNING: Sometimes an API is not available between systems. Confidential
19. Web Services When two systems cannot be integrated or an external client wants to get access one of the system say Expedia would like to access available rooms; then we define a middleware service for users/systems to access data on Ashram application system. To implement the middleware we use web services which use open protocol over HTML. As the data is request/response and is transmitted over the web these services are called web services. Amazon and Google provide web services for external users/vendors. Confidential
20. Web Services 2 What are Web Services? Web services are application components Web services communicate using open protocols Web services are self-contained and self-describing Web services can be discovered using UDDI Web services can be used by other applications XML is the basis for Web services Reference: http://www.w3schools.com/webservices/ws_intro.asp Confidential
21. What is SOAP? SOAP is an XML-based protocol to let applications exchange information over HTTP. Or more simple: SOAP is a protocol for accessing a Web Service. SOAP stands for Simple Object Access Protocol SOAP is a communication protocol SOAP is a format for sending messages SOAP is designed to communicate via Internet SOAP is platform independent SOAP is language independent SOAP is based on XML SOAP is simple and extensible SOAP allows you to get around firewalls SOAP is a W3C standard Confidential
22. What is WSDL WSDL is an XML-based language for locating and describing Web services. WSDL stands for Web Services Description Language WSDL is based on XML WSDL is used to describe Web services WSDL is used to locate Web services WSDL is a W3C standard Confidential
23. What is UDDI? UDDI is a directory service where companies can register and search for Web services. UDDI stands for Universal Description, Discovery and Integration UDDI is a directory for storing information about web services UDDI is a directory of web service interfaces described by WSDL UDDI communicates via SOAP UDDI is built into the Microsoft .NET platform Confidential
24. What is REST? A RESTful web service (also called a RESTfulweb API) is a simple web service implemented using HTTP and the principles of REST. It is a collection of resources, with four defined aspects: the base URI for the web service, such as http://example.com/resources/ the Internet media type of the data supported by the web service. This is often JSON, XML or YAML but can be any other valid Internet media type. the set of operations supported by the web service using HTTP methods (e.g., POST, GET, PUT or DELETE). The API must be hypertext driven Confidential
25. Web Services Summary Web services elements are SOAP, WSDL and UDDI which communicate between applications over HTML protocol using XML based requests and responses. REST is also a different kind of web services which uses as end-points a URL. The best example of REST service is the web. Confidential
27. A Use Case Confidential External Vendors Guest Requests Tickets TicketMaster System creates request Sends to middleware
28. Web Services Over twelve years of experince in various industries implementing integration of different systems and applications using web services, middleware programs. Trained technical and non-technical personnel on web services, middleware technologies etc. Some clients who have benefitted : ResortQuest Comcast, WildBlue, CenturyLink HP, Motorola, Nextel. Confidential