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Re: do not filter your customers
From: "Dobbins, Roland" <rdobbins () arbor net>
Date: Sat, 25 Feb 2012 03:52:56 +0000

On Feb 25, 2012, at 9:39 AM, Christopher Morrow wrote:

it seems to me that most of the options discussed for this are .. bad, in one dimension or another :(


X prefixes/packets in Y seconds/milliseconds doesn't keep the peer from blowing up your RIB,

How so?  If the configured parameters are exceeded, stop accepting/inserting updates until this is no longer the case.  
Exceptions would be made for peering session establishment, it would take effect after that.

it does slow down convergence :(

Yes, but is this always necessarily a Bad Thing?  For example, this particular circumstance (and many like it, c.f. 
AS7007 incident, et. al.)  it could be argued that in this particular case, [incorrect?  undesirable?  premature? 
pessimal?] convergence led to a poor result, could it not?

If you have 200 peers on an edge device, dropping the whole device's routing capabilities because of one 
AS7007/AS1221/AS9121 .. isn't cool
to your network nor the other customers on that device :(

Apologies for being unclear; I wasn't suggesting dropping or removing anything, but rather refusing to further 
accept/insert updates from a given peer until the update rate from said peer slowed to within configured parameters.

max-prefix as it exists today at least caps the damage at one customer.

But it doesn't, really, does it?  The effects cascade in an anisotropic manner throughout a potentially large transit 

The knobs available are sort of harsh all the way around though today :(

Concur again, sigh.

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

          Luck is the residue of opportunity and design.

                       -- John Milton

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