 The spillback behavior requires modeling the entire metropolitan area to recognize all of the upstream and downstream effects from intentional or unintentional perturbations to the network.
<clarity>  The spillback behavior requires modeling the entire metropolitan area to recognize all of the upstream and downstream effects from intentional or unintentional perturbations to the network.
 The spillback behavior requires modeling the entire metropolitan area to recognize all of the upstream and downstream effects on the network.