What is a web service?
In simple word web services is a collection of standards or
protocols for exchanging information between two devices or applications. Web
service is language independent way of communication. We just look bellow figure
to more clear our concept.
In above figure you can see java can communicate to other
languages like .net, PHP and vice versa by using web services i.e. web services
has no language limitation.
Types of Web Services
There are mainly two types of web services.
- SOAP web services.
- RESTful web services.
SOAP Web Services :-
SOAP stands for Simple Object Access Protocol. It is a
XML-based protocol for accessing web services.
SOAP is a W3C recommendation for communication between two
applications.
It is platform independent and language independent. By
using SOAP, you will be able to interact with other programming language
applications.
Advantages of Soap Web Services
WS Security: SOAP defines its own security known as WS
Security.
Language and Platform independent: SOAP web services can be
written in any programming language and executed in any platform.
Disadvantages of Soap Web Services
Slow: SOAP uses XML format that must be parsed to be
read. It defines many standards that must be followed while developing the SOAP
applications. So it is slow and consumes more bandwidth and resource.
WSDL dependent: SOAP uses WSDL and doesn't have any
other mechanism to discover the service.
Web Service Components
- SOAP
- WSDL
- UDDI
SOAP: SOAP is an acronym for
Simple Object Access Protocol.
WSDL: WSDL is an acronym for Web Services
Description Language. WSDL is pronounced as wiz-dull.
WSDL is a xml document containing information about web
services such as method name, method parameter and how to access it.
WSDL is a part of UDDI. It acts as a interface between web
service applications.
UDDI: UDDI is an acronym for
Universal Description, Discovery and Integration.
UDDI is a XML based framework for describing, discovering
and integrating web services.
UDDI is a directory of web service interfaces described by
WSDL, containing information about web services.
RESTful Web Services :-
REST stands for REpresentational State Transfer.
REST is an architectural style not a protocol.
Advantages of RESTful Web Services
Fast: RESTful Web Services are fast because there is
no strict specification like SOAP. It consumes less bandwidth and resource.
Language and Platform independent: RESTful web
services can be written in any programming language and executed in any
platform.
Can use SOAP: RESTful web services can use SOAP web
services as the implementation.
Permits different data format: RESTful web service
permits different data format such as Plain Text, HTML, XML and JSON
