Wikimedia Bugzilla is closed!

One consistent issue that admins on Wikipedia have been having is what to do
with blocking of IP ranges used by proxies. What usually happens is that
opportunistic vandals edit an article, but use a proxy range. Admins then block
the IP address for a period to stop the vandalism, but then we find that we've
blocked a considerable number of innocent editors. 

There are really two solutions to this issue that I can see:

1. Whitelisting of accounts from the IP block, or
2. The ability to limit the number of edits allowed to an article from an IP
range for a period of time (rate-limiting).

I personally favour the second option (partly because it's my baby, but mostly
because it solves the issue of slowing down vandalism but still allows editing
by anonymous editors.)

Rate-limiting would need the ability to be done individual IP addresses, a
discontiguous block of IP addresses, on a contiguous range of IP addresses, or
some sort of combination of all three. It would also be ideal to allow the admin
to set the number of edits over a specified period of time, or if that is too
great a judgement call, have a vandalism priority metric that sets that for us
(e.g. most severe: 2 edits allowed per article over 4 minutes; severe: 3 edits
allowed every five minutes; standard 6 edits every five minutes; low: 5 edits
every 3 minutes).