On 08/13/2013 12:14 AM, Graham Klyne wrote:
From: The IESG <iesg-secretary@xxxxxxxx>
To: IETF-Announce <ietf-announce@xxxxxxxx>
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Subject: Last Call: <draft-nandakumar-rtcweb-stun-uri-05.txt> (URI
Scheme for Session Traversal Utilities for NAT (STUN) Protocol) to
Proposed Standard
The IESG has received a request from an individual submitter to consider
the following document:
- 'URI Scheme for Session Traversal Utilities for NAT (STUN) Protocol'
<draft-nandakumar-rtcweb-stun-uri-05.txt> as Proposed Standard
The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
ietf@xxxxxxxx mailing lists by 2013-08-16. Exceptionally, comments
may be
sent to iesg@xxxxxxxx instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.
Abstract
This document is the specification of the syntax and semantics of the
Uniform Resource Identifier (URI) scheme for the Session Traversal
Utilities for NAT (STUN) protocol.
The file can be obtained via
http://datatracker.ietf.org/doc/draft-nandakumar-rtcweb-stun-uri/
IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-nandakumar-rtcweb-stun-uri/ballot/
No IPR declarations have been submitted directly on this I-D.
As IANA designated expert for reviewing URI scheme registrations, I've
been asked to approve this scheme for registration. If there is IETF
consensus to publish this document, it is clear to me that the scheme
should be registered.
But, in a personal capacity, not as designated reviewer, I have to ask
*why* this needs to be a URI. As far as I can tell, it is intended
for use only in very constrained environments, where there seems to be
little value in having an identifier that can appear in all the
contexts where a URI may be recognized.
The criteria for new URI schemes in http://tools.ietf.org/html/rfc4395
include:
"New URI schemes SHOULD have clear utility to the broad Internet
community, beyond that available with already registered URI schemes."
-- http://tools.ietf.org/html/rfc4395#section-2.1
This "utility to the broader community" is not clear to me, but I
don't fully understand the intended scope of this protocol, so I could
be missing something. So, in declaring consensus for this
specification, I would request that this aspect at least be considered.
I can only give my personal opinion....
1) This is a format for a piece of data. This data cannot be expressed
using any existing URI scheme - indeed, I don't think there exists
another well-defined textual representation of this piece of data.
1) This is defining an identifier that will be used in W3C-defined APIs.
W3C tends to use URIs every time they want a self-defining piece of data
with a clearly defined structure.
In the particular API where this is wanted, one wants to have STUN URIs,
TURNS URIs and TURN URIs passed over the same interface. Thus, keeping
with the W3C tradition of URIs seems reasonable.
I think this answers the question about "utility to the broader
community" to my satisfaction - your mileage may differ, of course.
...
Further, according to http://tools.ietf.org/html/rfc5389 it appears
that there are security considerations with regard to the STUN
protocol that it should not be used in isolation:
[[
Classic STUN also had a security vulnerability -- attackers could
provide the client with incorrect mapped addresses under certain
topologies and constraints, and this was fundamentally not solvable
through any cryptographic means. Though this problem remains with
this specification, those attacks are now mitigated through the use
of more complete solutions that make use of STUN.
For these reasons, this specification obsoletes RFC 3489, and instead
describes STUN as a tool that is utilized as part of a complete NAT
traversal solution.
]]
-- http://tools.ietf.org/html/rfc5389#section-2
It seems to me that creating a URI for STUN could encourage its use in
environments outside the "more complete solutions that make use of
STUN". This seems to be further reason that STUN[S] should not be a
URI scheme.
I have also suggested that, if registered, the URI scheme registration
should carries a "health warning" to this effect, and that it is not
suitable for general use that is not part of a "complete NAT traversal
solution". But I also recognize that I do not fully grasp the
security implications, and that if those that do know better can agree
that there is no potential for creating security risks here, this
suggestion may be unnecessary.
This URI scheme does not represent STUN. It represents configuration
data that is used to initialize a protocol machine that utilizes STUN.
This configuration data has to be passed no matter what the format of
the data is - whether it be URI or not.
Thus, I do not think the argument raised is really relevant to the
context. The data will be passed, and registering an URI scheme will
cause no more and no less data to be passed.
Again, my opinion.