The binding component Application Variables property allows you to define a list of name:value pairs for a given stated type. The application variable name can be used as a token for a WSDL extensibility element attribute in a corresponding binding. For example, if you were defining an application variable for the hostname as FOO, then the WSDL attribute would be ${FOO}. In the Application Variables property you would enter a String value of FOO for the name, and the desired attribute as the value. When you deploy an application that uses application variables, any variable that is referenced in the application's WSDL is loaded automatically.
The Application Variables configuration property offers four variable types:
Using Application Variables for password protection
To protect passwords that would otherwise appear as clear text in your WSDL file, you can enter a Password application variable as a token. In the following example, a password application variable is created that uses the name SECRET and the password PROTECT.
Variables also allow greater flexibility for your WSDL files. For example, you can use the same WSDL for different operating systems by using application variables to specify system specific information. These values can then be changed from the binding component runtime properties as needed, for any specific system.