Space-based architecture
A Space-based architecture (SBA) is an approach to distributed computing systems where the various components interact with each other by "exchanging" tuples or entries via one or more shared spaces. This is contrasted with the more common Message queuing service approaches where the various components interact with each other by "exchanging" messages via a message broker. In a sense, both approaches exchange messages with some central agent, but how they exchange messages is very distinctive. An analogy might be where a message broker is like an Academic conference, where each presenter has the stage, and presents  in the order they are scheduled; whereas a tuple space is like an Unconference, where all participants can write on a common whiteboard concurrently, and all can see it at the same time. A key goal of both approaches is to create loosely-coupled systems that minimize configuration, especially shared knowledge of who does what, leading to the objectives of better availability, resilience, scalability, etc. More specifically, an SBA is a distributed-computing architecture for achieving linear scalability of stateful, high-performance applications using the tuple space paradigm. It follows many of the principles of representational state transfer (REST), service -oriented architecture (SOA) and event-driven architecture (EDA), as well as elements of grid computing. With a space-based architecture, applications are built out of a set of self-sufficient units, known as processing-units (PU). These units are independent of each other, so that the application can scale by adding more units. The SBA model is closely related to other patterns that have been proved successful in addressing the application scalability challenge, such as shared nothing architecture (SN), used by Google, Amazon.com and other well-known companies. The model has also been applied by many firms in the securities  industry for implementing scalable electronic securities trading applications. History. Space-based architecture (SBA) was originally invented and developed at Microsoft in 1997–98. Internally at Microsoft it was known as Youkon Distributed Caching platform (YDC). First large web projects based on it were MSN Live Search (released in Sept. 1999) and later MSN Customer marketing data store (multi-terabyte in-memory DB shared by all MSN sites) as well as a number of other MSN sites released in late 1990s and early 2000s. See US patents 6,453,404 and 6,449,695: and other patents based on these: Components of space-based architecture. An  application built on the principles of space-based architecture typically has the following components: Literature. Articles/papers, technical: