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Re: Recent NTP pool traffic increase


From: David <opendak () shaw ca>
Date: Mon, 19 Dec 2016 14:12:27 -0700

On 2016-12-19 1:55 PM, Jan Tore Morken wrote:
On Mon, Dec 19, 2016 at 01:32:50PM -0700, David wrote:
I found devices doing lookups for all of these at the same time
{0,0.uk,0.us,asia,europe,north-america,south-america,oceania,africa,europe}.pool.ntp.org
and then it proceeds to use everything returned, which explains why
everyone is seeing an increase.

Thanks, David. That perfectly matches the list of servers used by
older versions of the ios-ntp library[1][2], which would point toward
some iPhone app being the source of the traffic.

[1] https://github.com/jbenet/ios-ntp/blob/d5eade6a99041094f12f0c976dd4aaeed37e0564/ios-ntp-rez/ntp.hosts
[2] https://github.com/jbenet/ios-ntp/blob/5cc3b6e437a6422dcee9dec9da5183e283eff9f2/ios-ntp-lib/NetworkClock.m#L122


That would make sense - I see a lot of iCloud related lookups from these hosts as well.

Also, app.snapchat.com generally seems to follow just after the NTP pool DNS lookups. I don't have an iPhone to test that though.

Thanks,


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