web services 2

8/2/2019 Web Services 2

1/18


2/18

A sample processA sample process There is a database with up-to-date information aboutweather and need to be distributed worldwide

To do so, the weather information is published through aWeb Service which returns weather information related

to the provided zip code Client sends service request in the form of zip code and

receives a service response as weather information

Other Examples: Credit checking, stock quote and purchasing service


3/18

Weak Integration onWeak Integration on thethe

onW

eb ApplicationonW

eb ApplicationAirline

Web

Server

Car

Rental

Web

Server

Hotel

Booking

Web

Server

Corporat

e Travel

Web

ServerAirline GUI

Car Rental

GUI

Hotel Booking

GUICorporate Travel

GUI

Copy

Paste

Copy

Paste

CopyPaste

HTTP/HTM

L

HTTP/HTM

L

HTTP/HTM

L


4/18

ImprovedImproved Integration onIntegration on

the onW

eb Servicethe onW

eb ServiceAirline

Web

Server

Car

Rental

Web

Server

Hotel

Booking

Web

Server

Corporat

e Travel

Web

Server

Corporate Travel

GUI

HTTP/SOAP/X

ML

HTTP/SOAP/X

ML

HTTP/SOAP/X

ML


5/18

What is a Web Service?What is a Web Service? A web service is any piece of software, that provides some functionality,is available over the internet, and talks using standardized XML Let you = you OR any application OR just a piece of code OR

something else. Now..

You can talk to a web service over the network via HTTP, SMTP, FTP, BEEPand many other protocols.

When you talk to a web service, the talk part is done using XML in astandardized fashion. The current standardized fashion being XML-RPCand SOAP.

All stuff that a web service would do for you (functionality provided) andall things it would need from you to do so (expected input) is described inXML in a standardized way called WSDL.

Web services live in registries in a way such that the right one for the job

can be very easily found. This is made possible by another standardizedXML way called UDDI.

XML is the music which makes web services dance


6/18

Why Web Services????

But Why Web

Services?


7/18

This is WhyThis is WhyWeb service allows a developer to include functionality

into a program without needing to "reinvent the wheel"and without needing to know anything about the businessor complexity of the Web service that he or she is using(encapsulation)

Interoperability among distributed applications that spandiverse hardware and software platforms that facilitatesdeveloping heterogeneous set applications

Accessibility of applications through firewalls using Webprotocols

"It might help to think of Web services in terms of yourelectricity supply. You don't generate your own electricity,you just plug in there. The electricity is delivered in agreedstandard units and you have a meter telling you how muchis being consumed."


8/18

FewF

ew CClarificationslarificationsOnly data are transmitted using Web servicestechnology; Web services do not have a visualinterface, such as text boxes, radio buttons, and the

likeA website, like banking, offers service but not web

service they dont use programmatic interfacethat allows two applications to be integrated


9/18

Web ServicesWeb Services

ArchitectureArchitecture Involves more than one Web service

Discovery of service from a pool of services

ServiceProcesses

Once located, web service can be asked to 'describe itself'and tell what operations it supports and how to invoke it

Handled by the Web Services Description Language(WSDL)

ServiceDescription

Message passes between the client and the server

Simple Object Access Protocol (SOAP) specifies how to

format requests to the server, and how the server shouldformat its responses

Service

Invocation

Messages transmitted between the server and the client

HTTP used for this part, which is also used to accessconventional web pages on the internet

Transport


10/18

ComponentsComponents

UDDI

Universal Description, Discovery,and Integration

Phonebook-like directory service

(XML)-based registry forbusinesses worldwide to list

themselves on the Internet and amechanism to register and

WSDL

Web Service DescriptionLanguage

an XML based protocol forinformation exchange indecentralized and distributed

environments Language used to fully describe a


11/18

Web Service ComponentsWeb Service Components

SOAP

Simple Object Access Protocol

SOAP provides a way to communicatebetween applications running ondifferent operating systems, withdifferent technologies and programminglanguages.

Initiates conversations with a UDDI

Platform independent & languageindependent

Makes object access simple

Application creates a request block in

XML, supplying the data needed by theremote method as well as the location ofthe remote object itself

ebXML

e-business XML

defines core components, businessprocesses, messaging services,company data, etc.

Purpose of ebXML initiative is to enablean E-marketplace

Emphasis on business process such asdelivering a product rather thanbusiness documents such as purchaseorder

ebXML architecture is divided into three

layers: common business objects such as

name, address

business process

registry that enables companies toelectronically locate a businesspartner and obtain requirements tofacilitate the exchange of dataelectronically.


12/18

How does it work ??H

ow does it work ??Step 1: Customer searches for arequired web service (like in Google

Search)

Step 2: Reply received from

directory server about the location ofthe required service

Step 3:Ask the target server about

how to invoke the web service

Step 4: Web Service replies in alanguage called WSDL

Step 5: Request sent in SOAP

language for the query

Step 6: Web Service will replies with

a SOAP response


13/18

Business AdvantagesBusiness Advantages Cost and Time Efficiencies

o Businesses can focus on value addition as they are free from the burden of

complex, slow and expensive software development

o Internal applications can be made public

o Incremental development easy and cheap

o Bug detection and fixing easy as the code is easily readableo Boost productivity by reducing mundane manual processes

o Saves cost in purchasing proprietary software

Dynamic Business Interoperabilityo Allows fro new business opportunities

o Stitching together of software applications results in new business opportunities

Software Management as a Serviceo Platform and language independent

o Encapsulation feature allows decoupling of dynamic components and more

stable system components


14/18

Technical AdvantagesTechnical Advantages Lower Integration Time and Cost

o Application integration faster and cheaper as products are inherentlycompatible

o Web services accessible by wide variety of communication devices over

internet

Rapid Integration of Legacy Systemso Integrates disparate legacy systems with newer applications

Reduced Need For Internal Human Resources Due ToLess Coding Requirementso Third party vendor provides web services which reduces need for application

programmers internally, thus increasing bottom line

o SaaS implementation helps in following ways:

Saves from the hassles of installation

Save money by leasing or renting a software for limited period

Updates provided by vendors which keeps the systems updated

Simplifies development, thus giving high returns on the investment


15/18

Practical ExamplesPractical Examples

The state of New Mexico, for example, is creating aWeb portal that allows employees to see and tailortheir personal information on a single Web page -

everything from pay checks to retirement plans.The application uses Web-Services technology inthe background to tie together legacy systems,including mainframes, that hadn't been able tocommunicate before.


16/18


17/18

Thank YouThank You

Questions?


18/18

http://www.ibm.com/developerworks/websphere/library/techarticles/0307_ryman/ryman.html

http://www.computerworld.com/s/article/94886/Bo

ok_Excerpt_When_to_Use_Web_Services?taxonomyId=11&pageNumber=7

http://cnettv.cnet.com/amazon-com-ceo-talks-

web-services/9742-1_53-24640.html

web services 2

Documents