Comcast using private space and trying to use pool.ntp.org

Tue Jul 9 23:02:21 UTC 2013

This is a friendly note to any Comcast net admins who might be interested:

We have a Business Fiber circuit and run a public NTP server in the pool.
It seems Comcast is using private IP space (mostly 10.29.0.0/16 and
10.183.0.0/16) for equipment and are trying to use the NTP pool for time
services (without NAT). Clearly that isn't working out so hot - my firewall
logs are chalk full of requests from those two networks, so I'd assume it's
a pretty large number of misconfigured devices since I'm one of many many
pool servers - and it's fairly safe to assume they're Comcast devices since
they aren't getting eaten before hitting my firewall from Cocmast. Just for
laughs, I suspect, Comcast blocks bogons at my gateway, so I couldn't even
let them get time from me if I wanted to.

Clearly not a critical (to me) issue, but I figured it was worth passing
along since I count on Comcast for interwebs and it's likely Comcast could
see time sync issues related to this.

Sincerely,
Mike McLaughlin