We are working on the 192.x.x.x swamp right now. Rough estimates (with much more accurate data @ NANOG)
60% - invalid or missing contact information
This is interesting. How about a policy that says if nobody can contact you and none of your addresses are reachable, then after some period, your addresses get recycled.
Interesting indeed. Lets see... Nobody can contact you .. is that the admin/tech contact, the administrative entity (corp, gov, agency etc) or ???? Addresses not reachable .. From which vantage point is this measuerment taken? Some period .. Like the 99 year lease on HongKong? Perhaps there is better wisdom out there on correct metrics for these values. From my limited viewpoint, the only way to recover the space is a voluntary return, based on the original allocation policies. There may be other incentives applied to facilitate the return, but strong-arm tactics and coersion, threats and hostile actions are not my favorites. I'd prefer to take almost any other action than blacklisting and hijacking. To take such actions, while it can be rationalized as a technological means to protect a networks internal stability, is presumptious and rude at best and legally indefensable at worst. Now if there are existant policies -in place-, that constrain the prefix handling, then your questions have been answered. Just my humble opinion. --bill