Filter NTP traffic by packet size?

Fri Feb 21 03:00:27 UTC 2014

On Feb 21, 2014, at 9:55 AM, Dobbins, Roland <rdobbins at arbor.net> wrote:

> Filtering out packets this size from UDP/anything to UDP/123 allows time-sync requests and responses to work, but squelches both the level-6/-7 commands used to trigger amplification as well as amplified attack traffic.

Also, the reverse - UDP/123 - UDP/anything, for the amplified attack traffic.

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Roland Dobbins <rdobbins at arbor.net> // <http://www.arbornetworks.com>

	  Luck is the residue of opportunity and design.

		       -- John Milton