Data distribution in embedded real-time sensor networks requires new protocols and programming environments that achieve time-sensitive message delivery and provide useful abstractions to the application programmer. Attainment of these goals requires changes to multiple layers of the communication protocol stack. In this paper, we review a protocol suite developed by the authors for data communication in embedded sensor networks. It takes into account time constraints and exports attribute-based connections that are tightly integrated with properties of the monitored environment. A programming language is described that allows external physical objects to be represented as first class abstractions in the computing system. The language facilitates writing monitoring applications. The system was implemented on a prototypical sensor network based on MICA motes.