 
Summary: Homogeneous Semantics Preserving
Deployments of Heterogeneous Networks of
Embedded Systems
Aaron D. Ames, Alberto SangiovanniVincentelli and Shankar Sastry
Center for Hybrid and Embedded Software Systems
Department of Electrical Engineering and Computer Sciences
University of California at Berkeley
{adames,alberto,sastry}@eecs.berkeley.edu
Summary. Tagged systems provide a denotational semantics for embedded sys
tems. A heterogeneous network of embedded systems can be modeled mathemati
cally by a network of tagged systems. Taking the heterogeneous composition of this
network results in a single, homogeneous, tagged system. The question this paper
addresses is: when is semantics (behavior) preserved by composition? To answer this
question, we use the framework of category theory to reason about heterogeneous
system composition and derive results that are as general as possible. In particular,
we define the category of tagged systems, demonstrate that a network of tagged
systems corresponds to a diagram in this category and prove that taking the com
position of a network of tagged systems is equivalent to taking the limit of this
diagramthus composition is endowed with a universal property. Using this univer
sality, we are able to derive verifiable necessary and sufficient conditions on when
