Not all any-casted prefixes are DNS resolvers and not all DNS resolvers are anycasted. It sounds like you would be better served by a list of well-known DNS resolvers. On Thu, Mar 21, 2019 at 12:35 PM Bryan Holloway <bryan@shout.net> wrote:
On 3/21/19 10:59 AM, Frank Habicht wrote:
Hi James,
On 20/03/2019 21:05, James Shank wrote:
I'm not clear on the use cases, though. What are the imagined use cases?
It might make sense to solve 'a method to request hot potato routing' as a separate problem. (Along the lines of Damian's point.)
my personal reason/motivation is this: Years ago I noticed that my traffic to the "I" DNS root server was traversing 4 continents. That's from Tanzania, East Africa. Not having a local instance (back then), we naturally sent the traffic to an upstream. That upstream happens to be in that club of those who don't have transit providers (which probably doesn't really matter, but means a "global" network).
/snip
Greetings, Frank
I can think of another ...
We rate-limit DNS from unknown quantities for reasons that should be obvious. We white-list traffic from known trusted (anycast) ones to prevent a DDoS attack from throttling legitimate queries. This would be a useful way to help auto-generate those ACLs.