Definition 4.2: Path Congestion Factor. We denote by λ the
path congestion factor, i.e., the total contention on any subflow path, as the sum of contention matrix elements that the
flow traverses through, i.e., λ =
N i=1
C(node i, direction j),
where N is the total number of nodes in the sub-flow path, node i the i-node through the path, and direction j the direction next to node i.