It seems thata hosts sending large amounts of NTP traffic over the
public Internet can be safely filtered if you don't already know that
it's one of the handful that's in the ntp.org pools or another well
known NTP master.
Speaking as one of the 3841 servers in the pool.ntp.org pool, I'm happy to be
described as a "handful," something my mother used to say, but I do feel
obligated to point out that it's a pretty big handful especially if you want
to be fiddling ACLs on an hourly basis which is pretty much what it takes.
I was thinking that the ntp.org servers on any particular network are a
small set of exceptions to a general rule to rate limit outgoing NTP
traffic.
Regards,
John Levine, [email protected], Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. http://jl.ly
