A network comprises a plurality of interconnected switches. At least one pair of switches is interconnected by a trunk formed from a plurality of individual links. A cost value is assigned to the trunk that is equal to the cost of one of the trunk's individual links. As such, a trunk is considered the same as an individual link when shortest path calculations are made. When multiple paths are computed as having the same lowest cost, the system balances load traffic between such lowest cost paths in a way that takes advantage of the higher bandwidth capabilities of trunks.