Primarily designed in order to separate the presentation layer and data in a REST-based model, ADO.NET Data Services are used to expose data as a service so they can be accessed via HTTP requests. You can use the standard HTTP verbs MERGE, GET, POST, PUT, and DELETE and perform CRUD (Create, Read, Update and Delete) operations against the service. ADO.NET Data Services expose the database schema in terms of XML metadata. It uses Atom and JSON data formats for data transfer over the HTTP protocol.
ADO.NET Data Services isolate the Data Access Layer and expose data via WCF services. We do not need to have the presentation layer as a consumer of a Data Services. We could also have another service as in SOA scenarios.
You can use ADO.NET Data Services to expose data through web services in terms of EDM abstractions such as Entity Data Model (EDM) objects. These objects can then be accessed by any application in much the same way as a web service is accessed....