The two canonical simulation paradigms in PGENESIS are
A third, hybrid, paradigm is embodied in the concept of zones. Within a zone, nodes run in the parallel mode, with PGENESIS performing automatic synchronization. The collection of zones runs in farm mode - synchronization is controlled from the scripts. This hybrid mode is useful for parameter searching on large models in which each instance of the model can be parallelized across a number of nodes. It may also be useful for a model of a system in which individual components, simulated in a zone, need only loose synchronization.
Zones can be thought of as a partition of the parallel platform in which no GENESIS messages can cross zone boundaries. Zones are established by the paron command, and are specified in other commands using the @ construct.