Certainly this data gives away *some* private information, but having that knowledge is often very useful when one discovers bizarre layer two problems. For instance, being able to ascertain that there is no packet loss from you to all devices on the same switch, and n% packet loss to all devices on another switch, without having to requests that MFS diagnose the apparent L3 problem, is very useful. Perhaps MFS could provide one unfiltered ping-responding device on each switch at a MAE? This would address diagnostic needs without requiring disclosure of other filtering issues. Besides, you can always tell who is reachable with a broadcast ping...