[56699] in North American Network Operators' Group
Re: Route Supression Problem
daemon@ATHENA.MIT.EDU (Vadim Antonov)
Wed Mar 12 14:08:02 2003
Date: Wed, 12 Mar 2003 11:04:14 -0800 (PST)
From: Vadim Antonov <avg@kotovnik.com>
To: Randy Bush <randy@psg.com>
Cc: nanog@merit.edu
In-Reply-To: <E18t7I8-000Dyw-00@roam.psg.com>
Errors-To: owner-nanog-outgoing@merit.edu
On Wed, 12 Mar 2003, Randy Bush wrote:
> > You need at least three flaps to trigger dampening.
>
> i guess you really need to look at that pdf.
>
> randy
"Better Algorithms" --
http://www.kotovnik.com/~avg/flap-rfc.txt
http://www.kotovnik.com/~avg/flap-rfc.ps
I didn't publish that one because I wanted to compare that with
penalty-based dampening on historical (pre-dampening) flap records, but
then got distracted by other projects. Preliminary data (from frequency
analysis) indicates that "unwarranted downtime" (defined as suppression
after the last flap prior to entering stable state) is reduced by a factor
of 3 to 4 compared with penalty-based algorithm tuned to produce the same
post-dampening flap rate.
--vadim
