I present the investigation involving two extensions of the cellular automaton based NagelSchreckenberg model, the Velocity-Dependent-Randomisation (VDR) model, and the two-lane model for symmetric and asymmetric lane changing rule sets. The study of the VDR model outlines a potential method in extending the lifetime of a metastable state and consequently postponing an inevitable traffic jam by orders of magnitude. The two lane model produces a so called "critical" and "sub-critical" flow which combined cause the collapse of flow at a critical density.
