Subject: [rtcweb] Ben Campbell's Yes on draft-ietf-rtcweb-security-arch-18: (with COMMENT)

From: Ben Campbell <[email-masked]>
Date: Mon, 04 Mar 2019 19:49:27 -0800

Ben Campbell has entered the following ballot position for
draft-ietf-rtcweb-security-arch-18: Yes

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COMMENT:
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I'm balloting "yes", but have a few minor comments and editorial comments:

§1:
- (nit) The first sentence will not age well; I gather RTCWEB will close before
long. (also The WG acronym is RTCWEB, not WebRTC. Or are you talking about the
W3C?)

- (nit) Figure 2: It seems a bit weird to have XMPP here, but never mentioned
in the text. At least, please expand the abbreviation somwhere. (It also shows
up in figure 4.)

(nit) §3.1, first bullet: While I don't normally object (beyond nose holding,
anyway) to the use of first person in RFCs, it seems an odd choice for this
sentence. I assume "we" in this sentence does not refer to the the author or
the WG.

 §4.1:
(nit) - '... button next to Bob’s name which says "Call".':
s/which/that

- "The calling site will also provide some user interface
element (e.g., a button) to allow Bob to answer the call, though this
is most likely not part of the trusted UI."

This is the first mention of "trusted UI". It would be helpful to elaborate on
that prior to this mention.

§5.1.4:
- "In this
case, the established identity SHOULD be applied to existing DTLS
connections as well as new connections established using one of those
fingerprints."

Applied by the recipient? (consider active voice). Also, why not MUST? Don't
unexpected things happen if the recipient doesn't do this?

§6.2:
- "Because HTTP origins cannot be securely established against network
attackers, implementations MUST NOT allow the setting of permanent
access permissions for HTTP origins. Implementations MUST refuse all
permissions grants for HTTP origins."

(nit-ish) - The MUST NOT seems non-constraining considering the last sentence.
Or am I reading that sentence wrong?

(nit) - .E.g., "Call [email-masked]"' : sentence fragment.
(nit) - ".. unlikely that browsers would have an X.509 certificate..." : Plural
disagreement (assuming the browsers do not share 1 cert).

(maybe nit) - "Clients MAY permit the formation of data channels without any
direct user approval." Is the switch from talking about "the browser" to
"Clients" intentional?

§6.4:
(nit) - "Note that these requirements are NOT intended..."
"NOT" in all caps is likely to be confused with 2119/8174 language.

§6.5:
 (nit) - "Implementations MUST implement SRTP [RFC3711]. Implementations MUST
implement DTLS [RFC6347] and DTLS-SRTP [RFC5763][RFC5764] for SRTP
keying. Implementations MUST implement [RFC8261]."

Thank you for using the citation style that doesn't assume everyone has
memorized the RFC numbers. But why not do the same for 8261?

§7.2:
(nit) - First paragraph: Can there be a citation for the W3C API spec?

§7.1.4, SDP example:
We just had a report against draft-ietf-mmusic-sdp-simulcast claiming that
putting "t=" after "c=" is not legal. 4566 and 4566bis seem to support that. (I
realize that, if that's in fact an error, we've got it all over the place.)

(nit) §11: The first sentence is a fragment.

§13.1 (normative references)

(nit) - There's a reference to RFC 5234, but it is not cited in the text.

- Is there a reason to reference 5246 rather than 8446, which obsoleted it?

§13.2:
- seems like the jsep reference should be normative.