One of the major tenets of any cloud computing platform is elasticity, allowing systems to scale beyond certain limits of their current designs. With Federations, SQL Database delivers on that promise; it is a technology your SQL Database instances can use to scale over time based on size or performance bottlenecks.
You may have certain expectations about how this technology should work, one of which is likely to be transparency to your applications. You may expect that no code changes should be necessary to your existing applications if you were to use Federations. Like anything else, radical features like Federations ...