Multimodal applications require the acquisition and processing of massive amounts of information from multiple sensors. Because this process is beyond the capabilities of a single machine, we developed a sensor network data transport system that can employ the numerous computing devices required to perform the task. The computational and data acquisition processes are thus allocated to components spread across a network of systems. We present the NIST Smart Data Flow System II, which is a middleware layer that represents applications as data flow graphs, and transports information streams between the different computational components of the application. Categories and Subject Descriptors C.2.4 [Computers-Communication Networks]: Distributed Systems – Distributed Applications. General Terms Algorithms, Performance, Design, Standardization. Keywords Data Streams, Distributed Computing, Smart Data Flow, Smart Spaces, Multimodal Data Transport Infrastructure.