The link weights are preferably adjusted to reduce the cost of {TAIL ~ network operation} without increasing the imbalance in {HEAD ~ link utilizations} 
The link weights are preferably adjusted to reduce the cost of { TAIL ~ network operation } without increasing the imbalance in { HEAD ~ link utilizations }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD