Re: mss to pmtu clamping partially broken?

[Phil Dibowitz <phil@ipom.com>]

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On Mon, Jul 02, 2007 at 09:16:57PM +0200, Krzysztof Oledzki wrote:
>
>
> On Mon, 2 Jul 2007, Phil Dibowitz wrote:
>
>> On Mon, Jul 02, 2007 at 07:04:12PM +0200, Andreas Steinmetz wrote:
>>> Jan Engelhardt wrote:
>>>> Do you really need clamping? It's a hack, since TCP should do MSS 
>>>> negotiation
>>>> itself. (Of course it may happen that some routers are broken.) But 
>>>> usually not
>>>> for incoming packets.
>>>
>>> You never know when you hit ICMP blackholes, broken routers and other
>>> evil things. Better safe than sorry so clamping is the way to go for me.
>>
>> I encourage you to report PMTUD Blackholes to the MSS Initiative at
>> http://www.phildev.net/mss/
>
> Any chances for similar initiative for "SACK vandals"? ;)

There's already a counterpart for ECN blackholes, so I'm not opposed to it.
However, keeping up with new reports, re-testing existing offenders, etc.
takes up a good chunk of time, so I don't have the time to do it myself. I'm
happy to reference such a site, however.

Though - I'm not familiar with the problem of SACK vandals either. There
appears to be a thread on here, I'll go read it...

-- 
Phil Dibowitz                             phil@ipom.com
Open Source software and tech docs        Insanity Palace of Metallica
http://www.phildev.net/                   http://www.ipom.com/

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