  In many Big Data applications today, information needs to be actively shared
between systems managed by different organizations. To enable sharing Big Data
at scale, developers would have to create dedicated server programs and glue
together multiple Big Data systems for scalability. Developing and managing
such glued data sharing services requires a significant amount of work from
developers. In our prior work, we developed a Big Active Data (BAD) system for
enabling Big Data subscriptions and analytics with millions of subscribers.
Based on that, we introduce a new mechanism for enabling the sharing of Big
Data at scale declaratively so that developers can easily create and provide
data sharing services using declarative statements and can benefit from an
underlying scalable infrastructure. We show our implementation on top of the
BAD system, explain the data sharing data flow among multiple systems, and
present a prototype system with experimental results.
