What are ends, contract, address, and bindings?

What are ends, contract, address, and bindings?
The above terminologies are the core on which SOA stands. Every service must expose one or
more ends by which the service can be available to the client. End consists of three important
things where, what and how:-
• Contract (What)
Contract is an agreement between two or more parties. It defines the protocol how client should
communicate with your service. Technically, it describes parameters and return values for a
method.
• Address (Where)
An Address indicates where we can find this service. Address is a URL, which points to the
location of the service.
• Binding (How)
Bindings determine how this end can be accessed. It determines how communications is done.
For instance, you expose your service, which can be accessed using SOAP over HTTP or
BINARY over TCP. So for each of these communications medium two bindings will be created.
Below figure, show the three main components of end. You can see the stock ticker
is the service
class, which has an end hosted on www.soa.com with HTTP and TCP binding support and using
Stock Ticker interface type.