This paper concerns the development of low-cost solutions to address challenges in digital manufacturing (DM). Service Oriented Architectures (SOAs) are a promising approach for addressing the requirements of a low-cost DM architecture. Interaction between services in a SOA is facilitated by a connectivity technology, i.e., a framework for interoperable data exchange between heterogeneous participants. We review a variety of connectivity technologies according to their suitability for use in an SME manufacturer’s production environment, and we assess how they have been integrated into past architectures. We then provide insights into an incremental and modular architecture for manufacturing SMEs.