I worry especially when I can not clearly see a benifit to either cat or mice.

The current serial number format supports a maximum of 100 changes to the .com zone per day. If you store your zone as text files on a hard drive that is more than enough. But! What if you consider the zone to be a database and maybe even store it in RAM? In that case, you could update the zone every single time one of the .com entries is added or deleted. The performance impact of doing this to a zone stored in RAM is approximately nil. However, the DNS protocol requires a serial number that changes every time the zone changes. So the first step is to change the way a zone serial number is created. Then you deploy a DNS server architecture that runs entirely out of RAM. And then when all of this works smoothly, you start to increase the number of updates per day until you're doing it every 15 minutes or so. Then, finally, you go live with real-time updates. In fact, with the speed of today's hardware and RAID arrays it's probably worthwhile to do this even without holding the whole zone in RAM. Now do you see why changing the serial number would clearly benefit the cat? And can you see how this would even lead to possible future benefits for many of us mice? If you are going to attack Verisign, at least pick a weak point to target with your attack. --Michael Dillon