Re: [Idr] TCP & BGP: Some don't send terminate BGP when holdtimer expired, because TCP recv window is 0

Job Snijders <job@sobornost.net> Sat, 12 December 2020 16:54 UTC

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Date: Sat, 12 Dec 2020 16:54:20 +0000
From: Job Snijders <job@sobornost.net>
To: John Scudder <jgs=40juniper.net@dmarc.ietf.org>
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Subject: Re: [Idr] TCP & BGP: Some don't send terminate BGP when holdtimer expired, because TCP recv window is 0
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On Fri, Dec 11, 2020 at 08:03:11PM +0000, John Scudder wrote:
> To take the liberty of summarizing your wall of text :-) you’re saying
> that you believe BGP should tear down its session if it’s unable to
> send a message for the duration of the hold time. 

Wall of text you say... here is a lighthearted attempt to visually
explain how routes become stale routes on the Internet. ;-)

    http://sobornost.net/~job/bgp_holdtimer_tcp_deathgrip.gif

Sessions with broken peers are not torn down, which prevents much
needed WITHDRAW messages from being generated.

> Given that the conversation last time was inconclusive I think this is
> a good thing for the WG to discuss again. If you want to, you (or
> someone) could turn the idea into a short draft that updates RFC 4271,
> and we could have a WG adoption discussion about it. 

will do

Kind regards,

Job