The document discusses the evolution of service-oriented architecture (SOA) infrastructure from SOAP to enterprise service buses (ESBs), and introduces Service Component Architecture (SCA) as a reference architecture that takes SOA from infrastructure to service modeling. SCA defines a model for building distributed applications and services by allowing entities like services, components and references to be assembled independently of their underlying infrastructure. It supports various implementation technologies and programming languages. The status of ongoing SCA standardization efforts is also covered.