nal = ofputil_put_NXAST_LEARN(openflow);
nal->idle_timeout = htons(learn->idle_timeout);
nal->hard_timeout = htons(learn->hard_timeout);
nal = ofputil_put_NXAST_LEARN(openflow);
nal->idle_timeout = htons(learn->idle_timeout);
nal->hard_timeout = htons(learn->hard_timeout);