[Pce] Ben Campbell's Discuss on draft-ietf-pce-pceps-15: (with DISCUSS and COMMENT)

[Ben Campbell <[e-mail]>]

Ben Campbell has entered the following ballot position for
draft-ietf-pce-pceps-15: Discuss

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DISCUSS:
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-3.4, step 2: "Peer validation always SHOULD include a check on whether
   the locally configured expected DNS name or IP address of
   the peer that is contacted matches its presented
   certificate."

Why is that not a MUST? As it is, this need to at least discuss the risks
involved if you don't check the identity of the peer cert (here or in the
security considerations.)


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COMMENT:
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Substantive:

- I share Warren's question about why you chose STARTTLS over a dedicated port,
especially since the 2nd to last paragraph in 3.2 goes out of its way to
mention that. What were the tradeoffs involved that made adding the additional
protocol machinery more attractive than allocating a port number?

- 3.2: "Implementations MUST support SHA-256 as defined by [SHS] as
          the hash algorithm for the fingerprint."
Do you really intend "MUST support" (meaning you have to be able to handle
sha-256, but could allow other hashes) vs "MUST use"?

- 3.5: "Implementations
   that want to support a wide variety of trust models SHOULD expose as
   many details of the presented certificate to the administrator as possible
   so that the trust model can be implemented by the administrator."
"as much as possible" is pretty vague for the a 2119 SHOULD. Since the
following sentences also include a SHOULD along with considerably more detail,
I suggest dropping the SHOULD in this sentence, and leaving the one in the
following sentence.

- 3.6: Is the exponential backoff requirement part of the procedures in 5440?
The wording suggests that it is not. If so, it needs elaboration here.

Editorial:

- 3.2, paragraph 8: s/"... PCE MUST responds with..."/ "...PCE MUST respond
with..."

- 3.4 : "Negotiation of mutual authentication is REQUIRED."
Does that mean that the peers must elect to use mutual authentication, or that
if they want to use it, they must agree to do so? (The pattern persists
throughout the section, but the meaning seems more obvious for some of the
others.)

-3.5, 2nd to last paragraph: Please don't use 2119 keywords to describe
pre-existing or external requirements. They should be reserved for the
authoritative specification of a given requirement.

-5, 2nd paragraph: The first sentence does not make sense.