TWC (AS11351) blocking all NTP?

Glen Turner gdt at
Tue Feb 4 00:40:35 UTC 2014

On 4 Feb 2014, at 9:28 am, Christopher Morrow <morrowc.lists at> wrote:

> wait, so the whole of the thread is about stopping participants in the
> attack, and you're suggesting that removing/changing end-system
> switch/routing gear and doing something more complex than:
>  deny udp any 123 any
>  deny udp any 123 any 123
>  permit ip any any

Which just pushes NTP to some other port, making control harder. We’ve already pushed all ‘interesting' traffic to port 80 on TCP, which has made traffic control very expensive. Let’s not repeat that history.

 Glen Turner <>

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