requiring a developer to be expert in all the different
languages. SOAP is based on XML. Because most
programming languages today have libraries for working
with XML, SOAP can act as an intermediary specification
between the different applications.
SOAP uses XML to communicate between web services
and clients. Because SOAP is platform and operating
system independent, it can work with both Windows and
Linux platforms. SOAP messages, which typically consist
of the following four main components, are sent between
the web applications and the clients (see Figure 6-6):
Envelope
Header
Body
Fault (optional)Figure 6-6 SOAP Message Format
The SOAP envelope encloses the XML data and identifies
it as a SOAP message. The envelope indicates the
beginning and the end of the SOAP message. The next
portion of a SOAP message is the SOAP header, and it