Thank you, Comcast.

Roland Dobbins rdobbins at
Fri Feb 26 13:53:41 UTC 2016

On 26 Feb 2016, at 20:17, Nick Hilliard wrote:

>  If you block packets with udp src port=53 towards
> customers, you will also block legitimate return traffic if the
> customers run their own DNS servers or use opendns / google dns / etc.

Actually, what they're talking about is blocking packets *destined* for 
UDP/53 on broadband access networks, not *sourced from*.

Roland Dobbins <rdobbins at>

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