Subject: [Teas] Spencer Dawkins' Yes on draft-ietf-teas-pce-central-control-04: (with COMMENT)

From: Spencer Dawkins <[email-masked]>
Date: Sun, 27 Aug 2017 15:03:07 -0700

Spencer Dawkins has entered the following ballot position for
draft-ietf-teas-pce-central-control-04: Yes

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COMMENT:
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This topic is not my area (duh, but I mean knowledge, not AD responsibility),
and I learned enough to ballot Yes while reviewing.

I find myself wondering why it’s more helpful than some other architecture
drafts I’ve reviewed, and note that it’s also pretty close to a forward-looking
applicability statement for PCE (re:
https://tools.ietf.org/html/rfc2026#section-3.2). No action requested for this
document, but something for ADs to think about, when we’re thinking about
architecture documents in general.

I did see a couple of places that were not as clear to me as most of the
document was.

In
https://tools.ietf.org/html/draft-ietf-teas-pce-central-control-04#section-3.1.1,
the description is short, which could be fine, but meant I was guessing at a
lot of high-level details that I could dig out of
https://tools.ietf.org/html/draft-ietf-pce-stateful-pce-21 for myself, but it
might be helpful to include a couple of points, like whether the PCCs in this
technology are (always?) LSRs participating in the IGP (OSPF or IS-IS), and
whether the PCEs are (always?) either LSRs or servers also participating in the
IGP, and whether the IGP is (always?) used to set up LSPs, for readers who have
a (G)MPLS or MPLS-TE network now, to figure out how it maps at a high level to
what they already have. I’m guessing from
https://tools.ietf.org/html/draft-ietf-pce-stateful-pce-21#section-5.5, but I’m
guessing.

I’m not quite sure what to do with this part of the security considerations:

   In
   short, while the interactions with a PCE-based controller are not
   substantially different to those in any other SDN architecture, the
   security implications of SDN have not been fully discussed or
   described.  Therefore, protocol and applicability work around
   solutions for this architecture must take proper account of these
   concerns.

   It is expected that each new document that is produced for a specific
   use case will also include considerations of the security impacts of
   the use of a PCE-based central controller on the network type and
   services being managed.

If I’m reading this literally, it’s saying that we haven’t finished discussing
SDN security considerations in general yet, so each new document will consider
the security impact of a PCE-based central controller on the network type and
services being managed as an SDN. Is that what was meant?

If I’m reading the manageability considerations section correctly, perhaps it’s
worth pointing out what the extension story is for the IGPs that will be used
in some of the technologies discussed earlier in the document, if that’s part
of this work as well.