Re: WG Adoption request for draft-mirsky-bfd-mpls-demand

"Carlos Pignataro (cpignata)" <> Sat, 27 October 2018 15:45 UTC

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From: "Carlos Pignataro (cpignata)" <>
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Subject: Re: WG Adoption request for draft-mirsky-bfd-mpls-demand
Thread-Topic: WG Adoption request for draft-mirsky-bfd-mpls-demand
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Date: Sat, 27 Oct 2018 15:44:57 +0000
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Hi Xiao,

Thanks much for the quick response!

Please find my follow ups:

1. Sorry if I was not clear. Yes, RFC 5880 lists exemplary possible mechanisms to glean continued connectivity but requires the use of one. My question is: which mechanisms does this draft propose? Could it please be spelled out?

2. Again, apologies if I was not clean enough. I understand what the abstract says, but the quoted text says that live was needs to be checked for a node (egress LER) instead of the forwarding path. Does that mean ~ “of the forwarding path towards/upto the node”?

Thanks for your consideration.

Thumb typed by Carlos Pignataro.
Excuze typofraphicak errows

On Oct 27, 2018, at 01:07, "<>" <<>> wrote:

Hi Carlos,

My answers to your two questions are as follow:

  1.  In section 6.6 of RFC5880, just after the text you quoted, it says "One possible mechanism is the receipt of traffic from the remote system; another is the use of the Echo function." So I'm not sure what's your real concern.

  2.  In the abstract of this draft it says "This document describes procedures for using Bidirectional Forwarding Detection (BFD) in Demand mode to detect data plane failures in Multiprotocol Label Switching (MPLS) point-to-point Label Switched Paths." If you don't like the expression form of the text quoted by you, pls feel free to propose some text.

Best Regards,

Xiao Min

发件人:CarlosPignataro(cpignata) <<>>
抄送人:Jeff Haas <<>>;<> <<>>;
日 期 :2018年10月26日 12:04
主 题 :Re: WG Adoption request for draft-mirsky-bfd-mpls-demand
Scanning through the draft, two questions:

1. What is the underlying mechanism to check liveness such that Demand can be used?

   Demand mode requires that some other mechanism is used to imply
   continuing connectivity between the two systems.  The mechanism used

2. Is this draft testing liveness of a path or a node?

   In this state BFD peers MAY remain as long as the egress LER is in Up
   state.  The ingress LER MAY check liveness of the egress LER by
   setting the Poll flag.  The egress LER will respond by transmitting


— Carlos Pignataro

On Oct 19, 2018, at 9:59 PM,<> wrote:

I support WG adoption of this draft. Use of the demand mode for p2p LSP monitoring is feasible and required.

Best Regards,

Xiao Min

发件人:JeffreyHaas <<>>
收件人<> <<>>;
日 期 :2018年10月18日 06:24
主 题 :WG Adoption request for draft-mirsky-bfd-mpls-demand
Working Group,

The BFD chairs have received an adoption request for
"BFD in Demand Mode over Point-to-Point MPLS LSP"

The adoption call will end on the Friday after IETF 103, November 9.

Note that there is are existing IPR statements on this draft:

Please indicate to the mailing list whether you support adoption of this

-- Jeff & Reshad