If you can let these computers flush trough a keyproxy, you can see how much blocks were flushed via that proxy. You could configure the computers on a certain IP to flush trough a certain keyproxy and computers on another IP to another proxy. You can look up de stats of each proxy separately.
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You can ofcourse also set up your own keyserver. I _think_ you can check the amount of blocks flushed by each individual IP. Check
www.keyserver.org on available keyservers (none yet for AT

) or on hoe to set up your own keyserver...
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