assume, your router directly plugged into ether on a isp's switch. assume, some nasty guy on the same segment trying to waste your PHYSICAL bandwidth by sending broad- or multicasts. yes, your packet filter will drop them, but prior to drop, stack must RECEIVE them and pf must recognize them as "to be dropped".
now, your PHYSICAL pipe is full of junk. so, Ed, explain me, how to shape down this junk?
