[v6ops] Spencer Dawkins' No Objection on draft-ietf-v6ops-pmtud-ecmp-problem-04: (with COMMENT)

["Spencer Dawkins" <[e-mail]>]

Spencer Dawkins has entered the following ballot position for
draft-ietf-v6ops-pmtud-ecmp-problem-04: No Objection

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COMMENT:
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In section 3, "Mitigation", I'm reading this.

   Mitigation of the potential for PTB messages to be mis-delivered
   involves ensuring that an ICMPv6 error message is distributed to the
   same anycast server responsible for the flow for which the error is
   generated.  Ideally, mitigation could be done by the mechanism hosts
               ^^^^^^^
   use to identify the flow, by looking into the payload of the ICMPv6
   message (to determine which TCP flow it was associated with) before
   making a forwarding decision.  Because the encapsulated IP header
   occurs at a fixed offset in the ICMP message it is not outside the
   realm of possibility that routers with sufficient header processing
   capability could parse that far into the payload.  Employing a
   mediation device that handles the parsing and distribution of PTB
   messages after policy routing or on each load-balancer/server is a
   possibility.
   
Most of the document is about using other mitigations that make this
mitigation unnecessary, but it's still a bit odd to see Deep Packet
Inspection characterised as "ideally", now that RFC 7258 is now BCP 188,
and we've chartered TCPINC to make that DPI fail as often as possible. 

Could that one word go away?

I see in email that Fred asked if any reviews were needed before
submitting this draft for publication, and David Black suggested reviews
from INT and TSV, and that made it as far as the shepherd writeup, but
I'm not seeing a request for review popping up in TSV (at least not with
"PMTUD" and "V6OPS" in an e-mail). I don't have concerns about this
particular draft, but I wish it hadn't slipped through that particular
crack. 

Yes, Fred copied TSVWG and TSVAREA on his note asking for guidance, and
yes, there was an IETF Last Call, so I'm not hitting "Defer" to chase
that. Just something to watch for, in the future.

And yes, Martin and I have a call set up to talk with the TSVdir triage
team next week ...