We have planned to create a bank loan application in Drupal. The Application does not have any own users records, but it completely depends on external service provider.
For example, when we log in to the application, the username and password should hit the service provider, and fetch the result from the provider; the login information should be validated into the application.
How do I implement the web service in Drupal? What type of modules do I need to use?
I need to be able to do CRUD operations using web services.