Google Apps Security and Compliance Services Web Services Application Programming Interface Guide, Early Access Version 1.5 - Manual (Page 12)

Introduction to Google Web Services API 9
When your application makes a web service request for data to the Google Web
Services API, the server authenticates your request and prepares the resulting
data. The server then sends a response, meaning the data is serialized and sent
across the Internet as a secure transaction to your application. The data is then
deserialized making it available to your web service application.
This is accomplished using standard protocols which define how the server and
client communicate, and how the data is recognized on the server-side and the
client-side of each transaction. The key components for this are the:
• WSDL -- The Web Service Description Language (WSDL) is an XML-
formatted description of the web service. It is a human-readable schema
definition. When you build your web service client application, your code will
include these WSDL descriptions which:
• Describe the constraints and attributes that can be used
• Describe the relationship of each element to other elements
• Describe the types of data used in the web service
These descriptions of values, identifiers, and relationships are the
schema’s binding definitions. This is how the Google Web Services API
server and your web service application understand how to communicate
with each other, and what that communication means.
• The Google Web Services API use the wrapped document literal binding
style for easy verification of the XML messages, and flexibility when the
system translates the WSDL bindings to a SOAP message.
• HTTPS -- Keeps your web service transaction secure
HTTPS messages transfer TCP/IP packets across the Internet to a secure
web server using a secure port. The session is encrypted by the Secure
Socket Layer (SSL) protocol. (Hypertext Transport Protocol/SSL is the full
name for HTTPS.)
• XML -- Guarantees the same content is accurately recreated on both the
server and the client no matter the differences in implementation language or
platform.