The most significant improvement in release 8 is that it allows modeling of networks with
oversaturated traffic conditions. Although release 7 accepted networks with these
conditions, it did not model them realistically. This is because the simulation process
applied in release 7 was not structured in such a way that spillback conditions could be
explicitly considered. Release 8 completely restructures the simulation process to address
these issues by changing from a link-wise approach to a step-wise approach.