Service-oriented architecture (SOA) is an architectural style designed for building distributed systems. The SOA actors are services: independent software packages that expose their functionality by receiving data (requests) and returning data (responses). SOA is designed to support the distribution of an application across computers and networks, which makes it a natural candidate for scaling on a cluster. The SOA support provided by Windows HPC Server 2008 R2 is based on Windows Communication Foundation (WCF), a .NET framework for building distributed applications. Windows HPC Server 2008 R2 SP2 improves SOA support by hosting WCF services on Windows Azure nodes in addition to the on-premises nodes.