A dataflow environment based on a client/server approach, called WiT, enables dataflow graphs to be executed efficiently with little overhead. Data tokens are managed by reference and reside on servers until either data is requested for viewing or required by another server. An enhanced
fire-on-any behaviour greatly simplifies the design of many simple graph constucts such as multiplexors or crossbars which are overly complicated when implemented with classical dataflow contraints.
Terence Arden, Joseph Poon, "A Dataflow Environment for Real-Time Image Processing Applications" in Proc. IS&T 2nd Color and Imaging Conf., 1994, pp 103 - 107, https://doi.org/10.2352/CIC.1994.2.1.art00028