Re: Mirja Kühlewind's Discuss on draft-ietf-bfd-multipoint-18: (with DISCUSS)

"Mirja Kuehlewind (IETF)" <> Thu, 05 July 2018 20:27 UTC

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Subject: Re: Mirja Kühlewind's Discuss on draft-ietf-bfd-multipoint-18: (with DISCUSS)
From: "Mirja Kuehlewind (IETF)" <>
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Date: Thu, 05 Jul 2018 22:26:09 +0200
Cc: Reshad Rahman <>,,, The IESG <>,
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To: Greg Mirsky <>
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Hi Greg,

just one thing quickly

> Am 05.07.2018 um 21:27 schrieb Greg Mirsky <>:
> 2) See sec 7 of RFC 8085
> "When BFD is used across multiple hops, a congestion control mechanism
>    MUST be implemented, and when congestion is detected, the BFD
>    implementation MUST reduce the amount of traffic it generates. "
> GIM>> I couldn't find this in RFC 8085 and had to broaden my search. I believe that thsi quote is from RFC 7880 Seamless BFD. I'm puzzled why this specification, when talking about challenges S-BFD may face, switches to requirement for BFD. Doesn't look right. And more, increasing transmission interval to avoid packet drop defeats the purpose of using proactive defect detection mechanism. The purpose of the fault management is to detect failures, not to avoid the detection. If active OAM generates excess of traffic, then other OAM mechanisms can be considered and used. But loosening OAM is not, in my view, proper way to address network problem as it rather hides them, not detets and reports as it intended to do. 
This quote is from RFC5880. The BFD base spec. Sorry that was copy and past error!