[tcpm] 793bis: dead gateway detection

Wesley Eddy <wes@mti-systems.com> Thu, 19 December 2019 22:01 UTC

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From: Wesley Eddy <wes@mti-systems.com>
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Date: Thu, 19 Dec 2019 17:01:30 -0500
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Subject: [tcpm] 793bis: dead gateway detection
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Gorry asked a question below about excessive TCP retransmissions 
resulting in triggering of whatever kind of lower-layer "dead gateway" 
detection logic might be available.  This comes from RFC 1122.  I don't 
know the current state of practice, or of any RFCs amending this, so am 
very interested in any feedback from the list on whether some change 
here is needed.

On 8/28/2019 11:39 AM, Gorry Fairhurst wrote:
> Section 3.8.3
> OLD:
>       pass negative advice (see [14]
>       Section 3.3.1.4) to the IP layer, to trigger dead-gateway
>       diagnosis.
> - Is this still best current practice? - If so please explain and cite 
> RFCs.