Using Pareto Principle to Improve the Efficiency for Selection of Qos Web Services

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USING PARETO PRINCIPLE TO IMPROVE THE EFFICIENCY FOR SELECTION

OF QoS WEB SERVICES

PROJECT REPORT

Submittedby

[email protected] Register No.: 283475184

SUBIKSHA.R Register No.: 283475144

VASANTHI.K Register No.: 283475161

Under the guidance of

Mr. PREM KUMAR

in partial fulfillment of the requirements for the degree

of

BACHELOR OF TECHNOLOGY

DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING

SRI MANAKULA VINAYAYAGAR ENGINEERING COLLEGE

MADAGADIPET, PUDUCHERRY-605107


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NOV-2010

SRI MANAKULA VINAYAGAR ENGINEERING COLLEGE

PONDICHERRY UNIVERSITY

DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING

BONAFIDE CERTIFICATE

This is to certify that the project work entitled USING PARETO PRINCIPLE TO

IMPROVE THE EFFICIENCY FOR SELECTION OF QoS WEB SERVICES is a

bonafide work done by [email protected] [Register No.: 283475184], SUBIKSHA.R

[Register No.: 283475144], AND VASANTHI.K [Register No.: 283475161] in partial

fulfillment of the requirement, for the award of B.Tech Degree in Computer Science and

Engineering by Pondicherry University during the academic year 2010-2011.

PROJECT GUIDE HEAD OF THE DEPARTMENT

Submitted for the University Examination held on ..

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INTERNAL EXAMINER EXTERNAL EXAMINER

ACKNOWLEDGEMENT

We are grateful to our Chairman Mr. N. KESAVAN. He has been a constant source of

inspiration right from the beginning.

We would like to express our faithful and grateful thanks to our Managing Director, Mr.

M. DHANASEKARAN for his support.

We would also like to thank our Vice Chairman Mr. S. V. SUGUMARAN, for providing

us with pleasant learning environment.

We would also like to extend our sincere gratitude and grateful thanks to our Principle,

Dr. V. S. K. VENGATACHALAPATHY for having extended the Research and Development

facilities of the department.

We also sincerely thank our Head of the Department, Mr. K. PREMKUMAR whose

continuous encouragement and sufficient comments enabled us to complete our project.

We are very thankful and grateful to our beloved guide, Mr. M. GANESAN whose great

support in valuable advices, suggestions and tremendous help enabled us in completing the first

phase of our project. He has been a great source of inspiration to us.

We thank all ourstaff members who have been by our side always and helped us with

our project.

We wish to thank our family members and friends for their constant encouragement,

constructive criticisms and suggestions with regards to this project review.

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Last but not the least; we would like to thank the ALMIGHTY for His grace and

blessings over us throughout the project.

ABSTRACT

With the rapid increase of Web Services, we can have a chance to select the best Qos

Web Service. To obtain the best QoS Web Service, a huge amount of computations on all the

candidate Web Services are required to computed. This will lead to less efficiency. To improve

selection performance, we use Pareto Principle to calculate only small part of Web Services

Here the client request for a particular Web Service. The Web Service Provider contains

already registered Web Services. The Web Service Discovery finds all the related Web Service

from the Web Service Provider and returns it to the client as response. By this way there is aproper interaction.

Input obtained from user/client (Service Requestor). The given input is matched with the

UDDI (Service Discovery). The matched Web Services are retrieved (Service Provider). Here

they are called Semantic Web Services. Reordering based on historical usage is done. First

twenty percent of the Semantic Web Services are obtained. They are termed as Candidate Web

Service. Candidate Web Service obtained are given back to user as response. Here in addition we

make use of the Pareto Principle. By using the Pareto Principle we can obtain the most

frequently used Web Services. Pareto Principle works on the concept of 80/20 rule (i.e) 80

number of people, 20 number of web services in use. The resulting Web Service is obtained

easily by using the Pareto Principle.

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TABLE OF CONTENTS

CHAPTER NO TITLE PAGE NO.

1 ABSTRACT 4

2 LIST OF FIGURES 6

3 LIST OF TABLES 7

4 LIST OF ABBREVATION 8

5 USING PARETO PRINCIPLE TO IMPROVE 9

THE EFFICIENCY FOR SELECTION OF QoS

WEB SERVICES

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LIST OF FIGURES

FIGURE NO NAME OF THE FIGURE PAGE NO

1 Model of Pareto principle based Qos Web Service selection 10

2 Web Service Working 12

3 Working of the Web Service using Pareto Principle 17

4 The Markup Language Pyramid 19

5 Pareto Principle Example 1 25

6 Pareto Principle Example 2 26

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LIST OF ABBREVATIONS

XML - eXtensible Markup Language

SOAP - Simple Object Access Protocol

WSDL - Web Services Description Language

UDDI - Universal Description, Discovery and Integration

Qos Quality of Service

WSP Web Service Provider

WSC Web Service Consumer

PQA - Pareto based Qos Authority

IOPE - Inputs Outputs Preconditions and Effects

HTTP Hypertext Transfer Protocol

TCP/IP Transmission Control Protocol

RPC Remote Procedure Call

COM Component Object Model

CORBA Common Object Request Broker Architecture

MIME Multipurpose Internet Mail Extensions

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CHAPTER 1

INTRODUCTION

The Web is a distributed, dynamic, and large information repository. It has now evolved

to encompass various information resources accessible worldwide. Organizations across allspectra have already moved their main operations to the Web, which has brought about a fast

growth of various Web applications. This has dramatically increased the need to build a

fundamental infrastructure for efficient deployment and access of the exponentially growing plethora of Web applications. The development of enabling technologies for such an

infrastructure is expected to change the business paradigm on the Web. Web services have

become de facto the most significant technological by-product. Simply put, a Web service is a piece of software application whose interface and binding can be defined, described, and

discovered as XML artifacts. It supports direct interactions with other software agents using

XML-based messages exchanged via Internet-based protocols. Examples of Web services

include online reservation, ticket purchase, stock trading, and auction. Standards are key enablersof Web services. Major industry players took a lead to set up crucial standards. This has greatly

facilitated the adoption and deployment of Web services. Three key XML-based standards have

been defined to support Web service deployment: SOAP, WSDL, and UDDI. SOAP defines acommunication protocol for Web services. WSDL enables service providers to describe their

applications. UDDI offers a registry service that allows advertisement and discovery of Web

services.

LITERATURE SURVEY

Compared with other models, the model of Pareto principle based Qos Web Service

selection uses Qos database and compute small part of quantity of Qos Web service to improve

performance. In figure 1, Web Service Provider(WSP) publishes Web Services and executes Web

Services; Web Service Consumer (WSC) requests service from registry centers, and consumes theQos Web Services; Pareto based Qos Authority(PQA) provides the quantification of Web Service

providers and consumers, and matches up the suitable Qos Web Services; UDDI is registry center

to register Web Services.

Compared with other models, this proposal uses Pareto principle to reduce the amount of

computations for selection of Qos Web Service. In this proposal, the selection of Web Services isdivided into four stages, which is described in detail in the following.

(1) The set of the possible Web Services in UDDI are Matched up according to the keywords of

required Web Service requested by Web Service consumers.

(2) The set of semantic Web Services is decided by matching up the Service Profiles whichdescribe the properties of a services, such as their functionalities and their set of inputs, outputs,preconditions and effects (IOPE).

(3) The set of semantic Web Services is reordered according to the numbers of historical usage.The first 20 percentage of semantic Web Services are chosen as candidate Web Services.

(4) The candidate Web Services are reordered according to Qos quantification formula. As

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various different kinds of Qos parameters, the parameters should be first changed into the norm

form, and calculated by the formula such as the paper.

Fig1: Model of Pareto principle based Qos Web Service selection

If all the candidate Web Services do not satisfy the Qos requirement of Web Service consumer,the rest of semantic Web Services are computed according to Qos quantification formula to find

the satisfied Web Services. Finally the Web Service with the first Qos quantification is selected asthe invoked Web Service.

EXISTING SYSTEM

In the existing system there is a major component namely XML web service.

XML Web Service

XML Web services are the fundamental building blocks in the move to distributed computing on

the Internet. Open standards and the focus on communication and collaboration among peopleand applications have created an environment where XML Web services are becoming the

platform for application integration. Applications are constructed using multiple XML Web

services from various sources that work together regardless of where they reside or how theywere implemented.

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There are probably as many definitions of XML Web Service as there are companies building

them, but almost all definitions have these things in common:

XML Web Services expose useful functionality to Web users through a standard Webprotocol. In most cases, the protocol used is SOAP.

XML Web services provide a way to describe their interfaces in enough detail to allow auser to build a client application to talk to them. This description is usually provided in an

XML document called a Web Services Description Language (WSDL) document. XML Web services are registered so that potential users can find them easily. This is

done with Universal Discovery Description and Integration (UDDI).

Why XML Web services

One of the primary advantages of the XML Web services architecture is that it allows programswritten in different languages on different platforms to communicate with each other in a

standards-based way. The first difference is that SOAP is significantly less complex than earlier

approaches, so the barrier to entry for a standards-compliant SOAP implementation issignificantly lower. You'll find SOAP implementations from most of the big software

companies, as you would expect, but you will also find many implementations that are built and

maintained by a single developer. The other significant advantage that XML Web services have

over previous efforts is that they work with standard Web protocolsXML, HTTP and TCP/IP.A significant number of companies already have a Web infrastructure, and people with

knowledge and experience in maintaining it, so again, the cost of entry for XML Web services is

significantly less than previous technologies.

We've defined an XML Web service as a software service exposed on the Web through SOAP,described with a WSDL file and registered in UDDI.

What with XML Web services

The first XML Web services tended to be information sources that you could easily incorporate

into applicationsstock quotes, weather forecasts, sports scores etc. It's easy to imagine a wholeclass of applications that could be built to analyze and aggregate the information you care about

and present it to you in a variety of ways; for example, you might have a Microsoft Excel

spreadsheet that summarizes your whole financial picturestocks, 401K, bank accounts, loans,etc. If this information is available through XML Web services, Excel can update it

continuously. Some of this information will be free and some might require a subscription to the

service. Most of this information is available now on the Web, but XML Web services will make

programmatic access to it easier and more reliable.

Exposing existing applications as XML Web services will allow users to build new, more

powerful applications that use XML Web services as building blocks. For example, a user might

develop a purchasing application to automatically obtain price information from a variety ofvendors, allow the user to select a vendor, submit the order and then track the shipment until it is

received. The vendor application, in addition to exposing its services on the Web, might in turn

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parts of the specification. If you have a well-formed XML fragment enclosed in a couple of

SOAP elements, you have a SOAP message.

All Web services use SOAP v1.1, a lightweight XML-based protocol optimized for use indistributed environments. SOAP v1.1 is designed to provide the necessary infrastructure and

definition to support XML-based Remote Procedure Calls. These optional parts of thespecification are used to implement RPC-style applications where a SOAP message containing a

callable function, and the parameters to pass to the function, is sent from the client, and theserver returns a message with the results of the executed function. Most current implementations

of SOAP support RPC applications because programmers who are used to doing COM or

CORBA applications understand the RPC style. SOAP also supports document style applicationswhere the SOAP message is just a wrapper around an XML document. Document-style SOAP

applications are very flexible and many new XML Web services take advantage of this flexibility

to build services that would be difficult to implement using RPC.

SOAP v1.1 provides the following:

An envelope for encapsulating a SOAP messageThis envelope might be an HTTP

MIME-encoded message provided to WebLogic Server or another application server via

HTTP, HTTPS, JMS, SMTP, FTP, or in some other way. A SOAP envelope typically

wraps not only the method request, but also its parameters. An example might be arequest to invoke a credit grant along with the user who should get the credit and the

credit limit.

A set of well-defined data and parameter encoding rulesBecause SOAP messagesmight be consumed by Web services written in any number of languages, a common set

of data-encoding rulesfor example, specifying strings, integers, and the likeis

required. Using the same credit request example, the name might need to be provided as a

string and the credit limit as an integer. A set of rules for describing methodsAs with data encoding, a predefined method

interface is required to make sure that both the requester and the supplier of information

understand and agree on what a call means. Examples of which could be the actualmethod name and argument list are described by the encoding rules.

What About Security?

One of the first questions newcomers to SOAP ask is how does SOAP deal with security. Early

in its development, SOAP was seen as an HTTP-based protocol so the assumption was made that

HTTP security would be adequate for SOAP. After all, there are thousands of Web applications

running today using HTTP security so surely this is adequate for SOAP. For this reason, thecurrent SOAP standard assumes security is a transport issue and is silent on security issues.

When SOAP expanded to become a more general-purpose protocol running on top of a number

of transports, security became a bigger issue. For example, HTTP provides several ways toauthenticate which user is making a SOAP call, but how does that identity get propagated when

the message is routed from HTTP to an SMTP transport? SOAP was designed as a building-

block protocol, so fortunately, there are already specifications in the works to build on SOAP to

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provide additional security features for Web services. The WS-Security specification defines a

complete encryption system.

WSDL

WSDL (often pronounced whiz-dull) stands for Web Services Description Language. For ourpurposes, we can say that a WSDL file is an XML document that describes a set of SOAP

messages and how the messages are exchanged. In other words, WSDL is to SOAP what IDL is

to CORBA or COM. Since WSDL is XML, it is readable and editable but in most cases, it isgenerated and consumed by software.

WSDL is the underpinning of how Web services are described to the outside world. Created by

Microsoft and IBM in 2000, WSDL defines an XML grammar for describing network services

and serves as a recipe for automating the details in application communication. Typically,WSDL describes a Web service's methods, inputs, and contact mechanism.

To see the value of WSDL, imagine you want to start calling a SOAP method provided by one ofyour business partners. You could ask him for some sample SOAP messages and write your

application to produce and consume messages that look like the samples, but this can be error-prone. For example, you might see a customer ID of 2837 and assume it's an integer when in fact

it's a string. WSDL specifies what a request message must contain and what the response

message will look like in unambiguous notation.

The notation that a WSDL file uses to describe message formats is based on the XML Schemastandard which means it is both programming-language neutral and standards-based which

makes it suitable for describing XML Web services interfaces that are accessible from a wide

variety of platforms and programming languages. In addition to describing message contents,

WSDL defines where the service is available and what communications protocol is used to talkto the service. This means that the WSDL file defines everything required to write a program to

work with an XML Web service. There are several tools available to read a WSDL file andgenerate the code required to communicate with an XML Web service. Some of the most capable

of these tools are in Microsoft Visual Studio .NET.

Many current SOAP toolkits include tools to generate WSDL files from existing program

interfaces, but there are few tools for writing WSDL directly, and tool support for WSDL isn't ascomplete as it should be. It shouldn't be long before tools to author WSDL files, and then

generate proxies and stubs much like COM IDL tools, will be part of most SOAP

implementations. At that point, WSDL will become the preferred way to author SOAP interfaces

for XML Web services.

These are the most important aspects of WSDL:

The methods provided by a Web service.

The inputs, outputs, and faults (errors) the defined methods return.

The mechanism used to contact the service.

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Web services are defined in terms of the endpoint, or service, that actually acts on or processes

the Web service's request. These endpoints represent the actual methods being implemented and

how they can be called. In reality, there are only two mechanisms for communicating with a Webservice: one-way and bidirectional, depending on who originated the message.

The WSDL specification defines four specific types of requests a Web service can support:

One-wayIn a one-way message, a service receives a message and may or may not act

on it. The client might get nothing back or might receive a result later in some unknownfashion.

Request/response In a request/response message, the service receives a request,

processes it, and returns a response.

Solicit/response In a solicit/response message, the end point sends a message andreceives a response.

NotificationIn a notification message, the Web service sends a message.

In fact, the only difference between one-way versus notification messages and request/responseversus solicit/response messages is who generates and sends the message. For example, in a one-

way message, the client makes a request, and the Web service acts on it without returning a

status. In a notification message, the Web service makes a call back to the client without waiting

for a response.

As you shall see shortly, WebLogic Workshop provides mechanisms for quickly and easily

developing Web services that support each request type.

UDDI

UDDI provides a mechanism for Web services developers to publish new and updated Webservices and a mechanism for clients to find and access published Web services. UDDI enablesbusinesses to publish and advertise the services they offer and describe how these services

should be used.

Web service functionality, as with most service-based functionality, is provided through a

programming interface specified in WSDL. In a publish-and-find scenario, a developer publishesthe existence of a service along with its definition, often referred to as a binding template. In a

picture-printing service, for example, any number of companies could offer a service to print

digital pictures. Binding templates contain one or more instances of a tModel, which representsinterfaces supported by the service. The tModel might have been uniquely published by the

service provider, with information on the interfaces and URL references to the WSDL document.

Universal Discovery Description and Integration is the yellow pages of Web services. As with

traditional yellow pages, you can search for a company that offers the services you need, readabout the service offered and contact someone for more information. You can, of course, offer a

Web service without registering it in UDDI, just as you can open a business in your basement

and rely on word-of-mouth advertising but if you want to reach a significant market, you needUDDI so your customers can find you.

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A UDDI directory entry is an XML file that describes a business and the services it offers. There

are three parts to an entry in the UDDI directory. The "white pages" describe the company

offering the service: name, address, contacts, etc. The "yellow pages" include industrialcategories based on standard taxonomies such as the North American Industry Classification

System and the Standard Industrial Classification. The "green pages" describe the interface to the

service in enough detail for someone to write an application to use the Web service. The wayservices are defined is through a UDDI document called a Type Model or tModel. In many cases,

the tModel contains a WSDL file that describes a SOAP interface to an XML Web service, but

the tModel is flexible enough to describe almost any kind of service.

The UDDI directory also includes several ways to search for the services you need to build yourapplications. For example, you can search for providers of a service in a specified geographic

location or for business of a specified type. The UDDI directory will then supply information,

contacts, links, and technical data to allow you to evaluate which services meet yourrequirements.

UDDI allows you to find businesses you might want to obtain Web services from. What if youalready know whom you want to do business with but you don't know what services are offered?

The WS-Inspection specification allows you to browse through a collection of XML Webservices offered on a specific server to find which ones might meet your needs.

At a minimum, a Web service must publish its business name and service information via

business registry entries. A business registry can contain the following:

Business identificationName, description of the business, contact information, and

other descriptive information. CategoriesStandard categorization information, such as Dun & Bradstreet's Data

Universal Numbering System (DUNS) numbers. Service descriptionNames and descriptions of the service given in the binding template

and custom category definitions given in the tModels, which contain binding information

for accessing the service at runtime to determine who actually implements a service.

UDDI also supports a wide variety of other information about the service, such as compliance

with a set of existing standards, usage details, transaction capabilities, and so forth.

What's Left

So far we've talked about how to talk to XML Web services (SOAP), how XML Web services

are described (WSDL) and how to find XML Web services (UDDI). These constitute a set ofbaseline specifications that provide the foundation for application integration and aggregation.From these baseline specifications, companies are building real solutions and getting real value

from them.

While much work has been done to make XML Web services a reality, more is needed. Today,

people are having success with XML Web services, but there are still things that are left as anexercise for the developer e.g. security, operational management, transactions, reliable

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messaging. The Global XML Web Services Architecture will help take XML Web services to

the next level by providing a coherent, general purpose model for adding new advanced

capabilities to XML Web services which is modular and extensible.

WS-Security is one of the specifications in the Global Web Services Architecture. Operational

management needs such as routing messages among many servers and configuring those serversdynamically for processing are also part of the Global Web Services Architecture, and are met by

the WS-Routing specification and the WS-Referral specification. As the Global Web ServicesArchitecture grows, specifications for these and other needs will be introduced.

PROPOSED SYSTEM

Fig 3: Working of the Web Service using Pareto Principle

The following are the steps in the determination of best Web Service selection done on basis of

Qos.

Input obtained from user/client (Service Requestor)

The given input is matched with the UDDI (Service Discovery)

The matched Web Services are retrieved (Service Provider)

Here they are called Semantic Web Services

Reordering based on historical usage is done

First twenty percent of the Semantic Web Services are obtained

They are termed as Candidate Web Service

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Candidate Web Service obtained are given back to user as response

Here in addition we make use of the Pareto Principle

By using the Pareto Principle we can obtain the most frequently used Web Services

Pareto Principle works on the concept of 80/20 rule

(i.e) 80 number of people

20 number of web services in use

The resulting Web Service is obtained easily by using the Pareto Principle

MODULES DESCRIPTION

UDDI

The Universal Description, Discovery, and Integration (UDDI) specification defines a SOAP-based Web service for locating Web services and programmable resources on a network. UDDI

provides a foundation for developers and administrators to readily share information about

internal services across the enterprise and public services on the Internet.

SEMANTIC WEB SERVICES

The objective of the Semantic Web Architecture is to provide a knowledge representation of

linked data in order to allow machine processing on a global scale. Currently, Web Services thatuse the .NET and J2EE frameworks are struggling to expand against the limitations of existing

Web architecture and conflicting proprietary standards. With software vendors battling for any

advantage, Semantic Web Services offer a giant leap forward; the first-time developer cansuccessfully exploit its latent potential to deliver such applications as semantic search, collective

email and collaborative Web word processing.

Why such a system?

Today, the data available within HyperText Markup Language (HTML) is difficult to manipulateon a large scale. Just think of information about plane schedules, baseball statistics, and product

purchasing information. While presently available at numerous sites, using this data in its HTML

form is problematic, even is eXtensible Markup Language (XML) is employed. The Semantic

Web offers an easier way to publish data that can be accessed and re-purposed as needed.

Semantic Web Services

For Semantic Web services to become a reality, a markup language must be descriptive enough

that a computer can automatically determine its meaning. The following is a list of tasks such a

language would be required to perform:

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Discovery: A program must first be able to automatically find, or discover, an

appropriate Web service. Neither the Web Service Description Language (WSDL) nor

the Universal Discovery and Description language (UDDI) allows for software todetermine what a Web service offers to the client. A Semantic Web service describes its

properties and capabilities so that software can automatically determine its purpose.

Invocation: Software must be able automatically to determine how to invoke or executethe service. For example, if executing the service is a multi-step procedure, the software

needs to know how to interact with the service to complete the necessary sequence. A

Semantic Web service provides a descriptive list of what an agent needs to do to be ableto execute and fulfill the service. This includes defining the inputs and outputs of the

service.

Composition: Software must be able to select and combine a number of Web services to

complete a certain objective. The services have to interoperate with each other seamlesslyso that the combined results are a valid solution.

Monitoring: Agent software needs to be able to verify and monitor the service properties

while in operation.

When Web markup languages evolve to the point that they can perform the above tasks,Semantic Web service can begin to prosper. You may be surprised to learn just how near the

W3C is to meeting these conditions.

Advanced Markup Languages

There are many ways in which the two areas of Web Services and the Semantic Web could

interact to lead to the further development of Semantic Web Services. Berners-Lee has suggestedthat both of these technologies would benefit from integration that would combine the Semantic

Web's meaningful content with Web Services' business logic.

Fig 4: The Markup Language Pyramid

Areas such as UDDI and WSDL are ideally suited to be implemented using Semantic Webtechnology. In addition, SOAP could use Resource Description Framework (RDF) payloads,

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remote RDF queries and updates, and interact with Semantic Web business rules engines,

thereby laying the foundation for Semantic Web Services.

The W3C is engaged in building the Pyramid of Web Markup Languages, which starts withHTML and XML and continues upward to include RDF and the most recent Web Ontology

Language (OWL). The off-spring of OWL is OWL for Services (OWL-S).

However, the technology issues of the Next Generation Web create many problematic questions

that must be solved before the full power and capability of the Semantic Web Services areavailable.

Concerns about logic loops, syntax errors and trust-worthy published information remain

formidable problems.

CANDIDATE WEB SERVICE

These are nothing but the Web Services that are used by the users of web in a frequent manner.The users of the web are termed as candidates here. Hence these Web Services are also known as

Candidate Web Services. Here the Candidate Web Service are dependent on the Semantic Web

Service in practice. The dependency is due to the fact that the Semantic Web Services are

reordered by using the factor of historical usage. This means that the most frequently used WebServices take up the first position so the order is in the descending order of usage. Once the

ordering is complete the first twenty percentage of the Semantic Web Services are chosen as the

Candidate Web Services.

PARETO PRINCIPLE OR 80/20 RULE:

What It Means

The 80/20 Rule means that in anything a few (20 percent) are vital and many(80 percent) are

trivial. In Pareto's case it meant 20 percent of the people owned 80 percent of the wealth. In

Juran's initial work he identified 20 percent of the defects causing 80 percent of the problems.Project Managers know that 20 percent of the work (the first 10 percent and the last 10 percent)

consume 80 percent of your time and resources. You can apply the 80/20 Rule to almost

anything, from the science of management to the physical world.

You know 20 percent of your stock takes up 80 percent of your warehouse space and that 80

percent of your stock comes from 20 percent of your suppliers. Also 80 percent of your sales will

come from 20 percent of your sales staff. 20 percent of your staff will cause 80 percent of your

problems, but another 20 percent of your staff will provide 80 percent of your production. Itworks both ways.

How It Can Help You

The value of the Pareto Principle for a manager is that it reminds you to focus on the 20 percentthat matters. Of the things you do during your day, only 20 percent really matter. Those 20

percent produce 80 percent of your results. Identify and focus on those things. When the fire

drills of the day begin to sap your time, remind yourself of the 20 percent you need to focus on.

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If something in the schedule has to slip, if something isn't going to get done, make sure it's not

part of that 20 percent.

There is a management theory floating around at the moment that proposes to interpret Pareto's

Principle in such a way as to produce what is called Superstar Management. The theory's

supporters claim that since 20 percent of your people produce 80 percent of your results youshould focus your limited time on managing only that 20 percent, the superstars. The theory is

flawed, as we are discussing here because it overlooks the fact that 80 percent of your time

should be spent doing what is really important. Helping the good become better is a better use ofyour time than helping the great become terrific. Apply the Pareto Principle to all you do, but use

it wisely.

Manage This Issue

Pareto's Principle, the 80/20 Rule, should serve as a daily reminder to focus 80 percent of your

time and energy on the 20 percent of you work that is really important. Don't just "work smart",work smart on the right things.

Pareto charts are used to graphically display the relative importance of groups or segments ofdata. This makes it easier to identify which problems are most important. Typically, the data

groups in a Pareto chart are displayed as a histogram or vertical bar chart, in descending order of

significance.

Pareto Analysis

Setting priorities for action

When faced with a range of issues, it is often difficult to know which to work on first. To resolve

this dilemna, the most useful thing to do is to apply Pareto's rule. This rule says - "eighty percent

of your troubles will come from 20 per cent of your problems". In other words, problems willrarely have equal impact, so it is best to first concentrate on the most important.

The value of this rule is not that it provides a scientifically accurate estimation of the weightings

which attach to a range of alternatives (which it does not), but simply that it is a reminder to

always look for 'the vital few' issues, and to separate them from 'the trivial many', before

attempting to solve problems. The next step is to identify which particular problems are the mostimportant. This is done by collecting appropriate data and displaying it in the form of a

histogram with each measured characteristic shown in descending order of magnitude. Such a

histogram is known as a Pareto chart. An example is shown below.

The high value items to the left hand side of the chart are the ones you need to concentrate on

first. Pareto's rule is also known as the 80/20 rule. It was named after Vilfredo Pareto who, in thelate 18th century, studied the distribution of wealth in Europe and found that 80% was held by

20% of the population. A number of well publicised business studies during this century showed

similar 80%/20% relationships, and claimed for example that, "managers spend only 20% of

their time to complete 80% of their work", and "80% of a company's business comes from 20%of its customers". These studies served to confirm the rule as an accepted part of management

folklore.

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Use the Rule whenever you need to make a choice

Apply Pareto's rule, and complete a Pareto chart, whenever a choice has to be made between anumber of alternative directions for action. This may be after an analytical exercise has been

completed to uncover the possible sources of a particular problem, or after a brainstorming

session to generate creative ideas to address an issue.

How to use the rule

After an analysis or ideas generating session, you will have a laundry list of items to evaluate. If

the list is a long one (say more than five or six items), try to get it down to a manageable size by

putting to one side any factors you reasonably suspect are of lesser significance. Don't discard

them entirely because without proper measurement you will never know for certain howsignificant the factors are. Better just to put them to one side and return to them later if the

selected alternatives don't prove successful. For the remaining factors, decide on the best way to

measure their relative significance and collect the data required. Plot the data on a histogram indescending order of importance.

Completing the histogram is particularly important if you are working with a team, or need tocommunicate the results of the data collection in a report or presentation. If you are working with

a team, the histogram becomes the focal point for discussing the validity of the findings and how

to pursue the issues involved.Listed step-by-step below is an example of the development of a

Pareto chart.

In this case, an analysis session was completed on the reasons why customers experienced undue

delays in delivery of their goods from the time a picking slip is generated in the warehouse. Thissession yielded a laundry list of possible causes.

picking errors

missing stock

sent to wrong address

part-supply refused

refused at delivery address/no receiving authority

goods returned/exceeded use-by date

goods returned/damaged

goods returned/servicing or preparation not done

goods mislaid by carrier

delivery delayed by carrier

goods returned/damaged in transit

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To reduce the list to a manageable number of items, some less likely causes were put aside and

others were aggregated to produce the following final list.

goods returned/incorrect items

goods returned/defective

goods returned/wrong address

goods not found in warehouse

A data collection program was then undertaken to find out how much time was being taken tocorrect these problems for the customer, and the results plotted in the histogram shown below.

The Pareto chart shows that the priority problem, the one causing greatest delays to customers, is

incorrect goods being sent.Reducing the incidence of this problem will yield the greatest benefit

to customers. After improvements have been made, another analysis can be made to determine ifthe problem has been reduced and confirm that "goods not found in the warehouse" is the next

most important problem to address.

Pareto Chart

Also called: Pareto diagram

Variations: weighted Pareto chart, comparative Pareto charts

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A Pareto chart is a bar graph. The lengths of the bars represent frequency or cost (time or

money), and are arranged with longest bars on the left and the shortest to the right. In this way

the chart visually depicts which situations are more significant.

When to Use a Pareto Chart

When analyzing data about the frequency of problems or causes in a process.

When there are many problems or causes and you want to focus on the most significant.

When analyzing broad causes by looking at their specific components.

When communicating with others about your data.

Pareto Chart Procedure

Decide what categories you will use to group items.

Decide what measurement is appropriate. Common measurements are frequency,quantity, cost and time.

Decide what period of time the Pareto chart will cover: One work cycle? One full day? A

week?

Collect the data, recording the category each time. (Or assemble data that already exist.)

Subtotal the measurements for each category.

Determine the appropriate scale for the measurements you have collected. The maximum

value will be the largest subtotal from step 5. (If you will do optional steps 8 and 9 below,

the maximum value will be the sum of all subtotals from step 5.) Mark the scale on theleft side of the chart.

Construct and label bars for each category. Place the tallest at the far left, then the nexttallest to its right and so on. If there are many categories with small measurements, they

can be grouped as other.

Steps 8 and 9 are optional but are useful for analysis and communication.

Calculate the percentage for each category: the subtotal for that category divided by the

total for all categories. Draw a right vertical axis and label it with percentages. Be sure

the two scales match: For example, the left measurement that corresponds to one-halfshould be exactly opposite 50% on the right scale.

Calculate and draw cumulative sums: Add the subtotals for the first and second

categories, and place a dot above the second bar indicating that sum. To that sum add the

subtotal for the third category, and place a dot above the third bar for that new sum.Continue the process for all the bars. Connect the dots, starting at the top of the first bar.

The last dot should reach 100 percent on the right scale.

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Pareto Chart Examples

Example 1 shows how many customer complaints were received in each of five categories.

Fig 7: Pareto Principle Example 1

Example 2 takes the largest category, documents, from Example #1, breaks it down into six

categories of document-related complaints, and shows cumulative values.

If all complaints cause equal distress to the customer, working on eliminating document-relatedcomplaints would have the most impact, and of those, working on quality certificates should be

most fruitful.

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Fig 8: Pareto Principle Example 2

SYSTEM REQUIREMENTS

1.HARDWARE SPECIFICATION

Distributed system and open environment a distributed system is a collection of independent

computers that appear to the users of the system as a single computer. And open environment is

defined as an environment where communication and data transfer can occur on remote system.

2.SOFTWARE SPECIFICATION

Visual studio .Net 2009 is the main software requirement which in turn needs some software

requirements as follows

Do you want to Windows XP

Windows Server 2003

Develop ASP Web applications and XMLWeb services

IIS (Internet Information Services)

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Compile code related to Microsoft Windows

Message Queuing (MSMQ)

Message Queuing Services

Debug code on remote computers Visual Studio Remote Debugger

Use source code control to version storedprocedures

Visual Studio 6.0 Stored Procedure VersioningVisual SourceSafe

Microsoft SQL Server

Table 1: Software Requirements for Visual Studio .net 2009

CONCLUSION

Qos plays an important role in Web Service selection in order to evaluate and rank candidateWeb services that are able to provide expected functionality. Similarly to the problem of Web

Service description, there may be various Qos models which are adopted by different service

providers and service requestors for describing Qos information. It is necessary to match

different Qos concepts such as Qos properties, metrices and units which are specified in a Qosadvertisement and a Qos requirement. Semantic technology has been applied in recent works

aiming to provide efficient and compatible method for describing and reasoning about Qos of

different systems. By using the Pareto Principle calculation of only small part of Web Service isdone and its performance is improved thereby.

FUTURE ENHANCEMENTS

The main future enhancement is that the entire process can be done in a real time application and

thereby showing as to how the performance and the efficiency of the Web Service is been

improved.

REFERENCES

[1] YUE Kun, WANG Xiao-Ling, ZHOU Ao-Ying. Underlying Techniques for Web Services: A

Survey. Journal of Software,2004,15(3):428442.

[2] Cardoso.Jorge,Sheth.etal. Quality of service for work ows and web service processes. Web

Semantics Science,Services and Agents on the World Wide Web,2004,1(3):281308.

[3] Anton J,Jacobs L,Liu X.Web caching for database applications with Oracle Web cache.

In:Frank- lin MJ,Moon B,eds.Proceedings of the 2002 ACM SIGMOD International Conference

on Mana- g ement of Data. New York: ACM Press, 2002. 594599.

[4] Kim SM, Rosu MC. A survey of public Web services. In: Feldman SI, uretsky M, Najork M,

Wills CE, eds. Proc. of the 13th Intl Conf. on World Wide Web (WWW 2004). New York: ACM

Press, 2004. 312-313.

[5] Yang shengli, Shi Meilin. A Model for Web Service Discovery with QoS Constraints. Journal

of Computer, 2005,28(4):589-594.

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[6] F. John Reh. Paretos Principle-The 80-20 Rule.

http://management.about.com/cs/generalmanage-ment/a/Pareto081202.htm. 2007.

[7] GUO De-keREN, YanCHEN Hong-huiXUE, Qun-weiLUO, Xue-shan. A Web Services

Selection and Ranking Model with QoS Constraints. JOURNAL OF SHANGHAI JIAOTONG

UNIVERSITY,2007 41(6):870- 875

[8] UDDI http://www.uddi.org/pubs/uddi v3.htm

[9] Eyhab Al-Masri ,Qusay H. Mahmoud. Discovering the Best Web Service. www2007.

http://www2007.org/posters/poster970.pdf

[10] Eyhab Al-Masri ,Qusay H. Mahmoud. A Framework for Efficient Discovery of WebServices across Heterogeneous Registries, IEEE Consumer Communication and Networking

Conference (CCNC) 2007.

Documents

Using Pareto Principle to Improve the Efficiency for Selection of Qos Web Services