Web Services
BlueBay Solutions have been developing custom web services for its clients for
some time now. This year they announce the release of 2 web services for
general use.
Click here for more
information
What is a Web Service
A web service is any piece of software that makes itself
available over the internet and uses a standardized XML messaging system. XML
is used to encode all communications to a web service. For
example, a client invokes a web service by sending an XML message, then waits
for a corresponding XML response. Because all communication is in XML, web
services are not tied to any one operating system or programming language--Java
can talk with Perl; Windows applications can talk with Unix applications.
Web services are simple, self contained applications which
perform functions, from simple requests to complicated business processes. The
"web services" model uses WSDL, UDDI
and SOAP/XMLP. A WSDL description is retrieved from
the UDDI directory. WSDL descriptions allow the software systems of one
business to extend to use those of the other directly. The services are invoked
over the World Wide Web using the SOAP/XMLP protocol. Each of the components is
XML based.
Where two agencies know about each other's web services they
can link their SOAP/XMLP interfaces - provided all security concerns are
managed appropriately. It is only where services are going to have unknown
users that they need to be formally described by a language such as WSDL and
entered into a directory such as UDDI.
WSDL
Web Services Definition Language (WSDL) describes how to use the software
service interfaces of a registered business over the Internet within the "web
services" model.
UDDI
Universal Description, Discovery and Integration (UDDI) provides
directory services to discover Internet-based business resources within the
"web services" model.
SOAP/XMLP
Simple Object Access Protocol (SOAP/XMLP) uses web protocols to exchange from
one computer to another. SOAP/XMLP specifies how to encode an HTTP header
and an XML file so that one computer program can call a program in
another computer and pass it information. It also specifies how to return a
response.
SOAP is a way for a program running in one kind of operating system (such as
Windows 2000) to communicate with a program in the same or another kind of an
operating system (such as Linux) by using the World Wide Web's Hypertext
Transfer Protocol (HTTP) and its Extensible Markup Language (XML) as the
mechanisms for information exchange. Since Web protocols are installed and
available for use by all major operating system platforms, HTTP and XML provide
an already at-hand solution to the problem of how programs running under
different operating systems in a network can communicate with each other. SOAP
specifies exactly how to encode an HTTP header and an XML file so that a
program in one computer can call a program in another computer and pass it
information. It also specifies how the called program can return a response.
