ALTQ - prioritizing by traffic type

Daniel Hartmeier's ADSL - prioritizing ACKs to improve up/download over asymmetric link

ext_if="kue0"

altq on $ext_if priq bandwidth 100Kb queue { q_pri, q_def }
queue q_pri priority 7
queue q_def priority 1 priq(default)

pass out on $ext_if proto tcp from $ext_if to any flags S/SA \
        keep state queue (q_def, q_pri)

pass in  on $ext_if proto tcp from any to $ext_if flags S/SA \
        keep state queue (q_def, q_pri)

See http://www.benzedrine.cx/ackpri.html