  Filtering packet traffic and rules of permit/denial of data packets into
network nodes are granted by facilitating Access Control Lists (ACL). This
paper proposes a procedure of adding a link load threshold value to the access
control list rules option, which acts on the basis of threshold value. The
ultimate goal of this enhanced ACL is to avoid congestion in targeted
subnetworks. The link load threshold value allows to decide that packet traffic
is rerouted by the router to avoid congestion, or packet drop happens on the
basis of packet priorities. The packet rerouting in case of high traffic loads,
based on new packet filtering procedure for congestion avoidance, will result
in the reduction of the overall packet drop ratio, and of over-subscription in
congested subnetworks.
