In this presentation, I covered the following topics: 1. Introduction to AJAX 2. How AJAX works 3. Web Services

2.  AJAX stands for Asynchronous JavaScript And
XML.
 AJAX is not a programming language.
 AJAX just uses a combination of:
• A browser built-in XMLHttpRequest object (to
request data from a web server)
• JavaScript and HTML DOM (to display or use the
data)

4. 1. Creating an instance of the XMLHttpRequest
object to send an HttpRequest from a client to a
server.
variable=new XMLHttpRequest();
2. Creating a request to a server by using the
open() method of the XMLHttpRequest object.
open(method,url,async);
3. Sending a request to a server by using the send()
method of the XMLHttpRequest object.
send(string);

5.  SOAP – Simple Object Access Protocol.
 It is an XML-based massaging protocol for
exchanging information among computers.

6.  SOAP is a communication protocol.
 SOAP can extend HTTP for XML messaging.
 SOAP provides data transport for web services.
 SOAP can be used for broadcasting a message.
 SOAP is platform independent.

7.  A SOAP message is an ordinary XML document
containing the following elements:
1. Envelope : Defines the start and end of the message.
2. Header : Contains any optional attributes of the
message used in processing the message, either at an
intermediary point or at the ultimate end-point.
3. Body : Contains the XML data comprising the
message being sent.
4. Fault : Provides information about errors that occur
while processing the message.

8. <?xml version=“1.0”?>
<SOAP-ENV:Envelop
xmlns:SOAP-ENV = “http://www.w3.org/2001/12/soap-envelope"
SOAP-ENV:encodingStyle = "http://www.w3.org/2001/12/soap-
encoding">
<SOAP-ENV:Header>
...
...
</SOAP-ENV:Header>
<SOAP-ENV:Body>
...
...
<SOAP-ENV:Fault>
...
...
</SOAP-ENV:Fault>
</SOAP-ENV:Body>
</SOAP_ENV:Envelope>

9.  WSDL – Web Services Description Language.
 It is the standard format for describing a web
service.
 WSDL was developed jointly by Microsoft and
IBM.

10.  WSDL is an XML-based protocol for
information exchange in decentralized and
distributed environments.
 WSDL definitions describe how to access a web
service and what operations it will perform.
 WSDL is a language for describing how to
interface with XML-based services.
 WSDL is the language that UDDI uses.

11.  The three major elements of WSDL:
1. Types : The data types to be used in the messages
are in the form of XML schemas.
2. Operations : It is the abstract definition of the
operation for a message.
3. Binding : It is the concrete protocol and data formats
for the operations and messages defined for a
particular port type.

12. <definitions>
<types>
definition of types........
</types>
<message>
definition of a message....
</message>
<portType>
<operation>
definition of a operation.......
</operation>
</portType>
<binding>
definition of a binding....
</binding>
<service>
definition of a service....
</service>
</definitions>

13.  UDDI – Universal Description, Discovery, and
Integration.
 UDDI is an open industry initiative, enabling
businesses to discover each other and define how
they interact over the Internet.
 UDDI has two sections:
1. A registry of all web services metadata, including a
pointer to the WSDL description of a service.
2. A set of WSDL port type definitions for manipulating
and searching that registry.

14.  It contains 3 elements are:
1. White Pages : Basic information about the company
and its business.
2. Yellow Pages : Contain more details about company.
3. Green Pages : Contain technical information about a
web service.

15.  UDDI Data Model :
It is an XML Schema for describing businesses and
web services.
 UDDI API Specification
It is a specification of API for searching and
publishing UDDI data.

16.  UDDI Cloud Services