The present invention relates generally to a software architecture for simulation of physical entities. The invention provides an object-oriented container-based framework architecture for simulator implementations, methods, and objects in a time domain on a distributed computer network and in field deployed units. The invention further provides an interface system and a plug-in definition which allows compartmentalization of participants in the container and easy extensibility of the system. A hierarchy of life-cycle containers having contained objects is disclosed. An object graph description is used by an assembly engine to construct an executable object graph including the hierarchy of life-cycle containers. Life-cycle containers can be implemented as LRU portable containers for field deployed units.