Representation of Uncertainty and Confidence in the Presence Information Data Format Location Object (PIDF-LO)
draft-ietf-geopriv-uncertainty-04

[Ballot comment]
This document is really well written, and was interesting to read; thanks.  And thanks for addressing the small points I had.

  Location generators SHOULD attempt to ensure that confidence is equal
  in each dimension when generating location information.  This
  restriction, while not always practical, allows for more accurate
  scaling, if scaling is necessary.

Thanks for that: this is how "SHOULD" ought always be specified.  I might remember this to use as an example.

[Ballot comment]
I remain completely spooked by the Geopriv work. I understand that I
am "in the rough" with my views and I understand that there are
implementations, etc., etc. But I still think that the privay issues
of Geopriv remain poorly addressed.

On that basis, I will not block this work, but I will also not support
it.

---

Abstract

  The key concepts of uncertainty and confidence as they pertain to
  location information are defined.  Methods for the manipulation of
  location estimates that include uncertainty information are outlined.

Are those general statements, or are they intended to refer to this
document?

[Ballot discuss]
An easy point, quickly fixed:

At the top of the document, you say that operator precedence is specified by parentheses, and give no other precedence mechanism.  In the formulae in Sections 5.1.1.1, 5.1.1.2, 5.2, and elewhere, you seem to be using the standard implicit precedence of multiplication over addition, or perhaps using spacing to indicate precedence.  I think you need to either say (up in Section 1.1) that you're doing that, or add more parentheses to the formulae.

It seems to me that it's be best to say more about operator precedence in 1.1, rather than to clutter the formulae throughout the document.

[Ballot comment]
This document is really well written, and was interesting to read; thanks.

I've only a small quibble in Section 4.2:

  Location generators SHOULD attempt to ensure that confidence is equal
  in each dimension when generating location information.  This
  restriction, while not always practical, allows for more accurate
  scaling, if scaling is necessary.

Thanks for that: this is how "SHOULD" ought always be specified.  I might remember this to use as an example.

  A confidence element MUST be included with all location information
  that includes uncertainty (that is, all forms other than a point).  A
  special "unknown" MAY be used if confidence is not known.

Here, on the other hand, I don't see how the "MAY" makes sense.  You MUST include confidence, even when you don't know what to inlude.  So if you don't know... what *else* can you use but "unknown"?  So I think it's not a "MAY be used", but an "is used".

[Ballot discuss]
The draft is well written and I do support it moving forward. 

This discuss will be cleared with the next update, thanks.

I don't see a discussion on privacy and would like to figure out if it needs to mention it or not.  Although the draft provides a way to represent certainty and confidence information on geolocation data, wouldn't the location coordinates be sensitive if combined with other information such as event types or people at the locations identified?  I think it would be good to mention that this data in and of itself is not privacy sensitive (we can pinpoint where the Sydney Opera house is located), but when combines with other information, it may become privacy sensitive information (a crime took place at the Sydney Opera House and it has not been announced yet and the people involved have not been identified).  You may not want news camera on the scene of certain events - rape victim still present.

Alissa suggested adding a reference BCP 160 since it applies whether or not location is certain, which works for me to resolve this question. 

Thanks.

[Ballot comment]

- I agree with Kathleen's point that a discussion of privacy
would be good. Perhaps if you could cover how
privacy-(un)friendliness might vary with uncertainty and
confidence that'd be good. Presumably privacy goes "up" as
uncertainty increases and "down" as confidence increases, at
least in some sense? Or if not, explaining why would be
good. I'd say a sentence or two in the security considerations
might be enough for that, perhaps with a warning that
its easy to go wrong when looking for "more" privacy.

- 3.1: This section just wasn't very clear to me. Could that
just be safely deleted? (Or the last para at least.)

- section 5, 1st bullet - does this really belong here? Its
fine to have it here, but I wondered if it'd really be
better somewhere else. (Not suggesting you re-open something
else but just wondered.)

- p15: ECEF is used without expansion

- 5.5: "In the absence of specific recommendations, this
document suggests that the probability be greater than 50%
before a decision is made. " That's not very clear to me. I
think you just mean that the default is to say yes, its in
the area of interest if the probability of that is >50%.

[Ballot comment]
2 - This section (and some of the longer explanations in other sections) made me curious who the target audience for this document is. I'm no stats guy, but I found the information in this section pretty straightforward, and thought that a simple pointer to a reference or just a list of definitions would probably have been enough. This document does seem to go on at length about some pretty basic topics. But maybe I'm not the average reader.

3.1 - "infinitesimally larger"?

4.1 - I'm not clear on the treatment of a confidence of "unknown". How does this affect implementations (as against a missing confidence)?

[Ballot discuss]
The draft is well written and I do support it moving forward. 

I don't see a discussion on privacy and would like to figure out if it needs to mention it or not.  Although the draft provides a way to represent certainty and confidence information on geolocation data, wouldn't the location coordinates be sensitive if combined with other information such as event types or people at the locations identified?  I think it would be good to mention that this data in and of itself is not privacy sensitive (we can pinpoint where the Sydney Opera house is located), but when combines with other information, it may become privacy sensitive information (a crime took place at the Sydney Opera House and it has not been announced yet and the people involved have not been identified).  You may not want news camera on the scene of certain events - rape victim still present.

Alissa suggested adding a reference BCP 160 since it applies whether or not location is certain, which works for me to resolve this question. 

Thanks.

IESG/Authors/WG Chairs:

IANA has reviewed draft-ietf-geopriv-uncertainty-03.  Please report any inaccuracies and respond to any questions as soon as possible.

IANA's reviewer has the following comments:

IANA understands that, upon approval of this document, there are two actions which need to be completed.

First, in the ns registry of the IETF XML Registry located at

https://www.iana.org/assignments/xml-registry/

a new namespace is to be registered as follows:

ID: geopriv:conf
URI: urn:ietf:params:xml:ns:geopriv:conf
Filename: [ TBD-at-registration ]
Reference: [ RFC-to-be ]

As this document requests registrations in an Specification Required (see RFC 5226) registry, IANA will initiate the required expert review via a separate request.

Second, in the schema registry also in the IETF XML Registry located at

https://www.iana.org/assignments/xml-registry/

a new schema is to be registered as follows:

ID: geopriv:conf
URI: urn:ietf:params:xml:schema:geopriv:conf
Filename: [ TBD-at-registration ]
Reference: [ RFC-to-be ]

Note that this is also a Specification Required (see RFC 5226) registry. IANA will initiate the required expert review via a separate request.

IANA understands that these two actions are the only ones required upon approval of this document.

Note:  The actions requested in this document will not be completed until the document has been approved for publication as an RFC. This message is only to confirm what actions will be performed.

The following Last Call announcement was sent out:

From: The IESG
To: IETF-Announce
CC:
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (Representation of Uncertainty and Confidence in PIDF-LO) to Proposed Standard


The IESG has received a request from the Geographic Location/Privacy WG
(geopriv) to consider the following document:
- 'Representation of Uncertainty and Confidence in PIDF-LO'
  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@ietf.org mailing lists by 2014-10-07. Exceptionally, comments may be
sent to iesg@ietf.org instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.

Abstract


  The key concepts of uncertainty and confidence as they pertain to
  location information are defined.  Methods for the manipulation of
  location estimates that include uncertainty information are outlined.

  This draft normatively updates the definition of location information
  representations defined in RFC 4119 and RFC 5491.  It also deprecates
  related terminology defined in RFC 3693.




The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-geopriv-uncertainty/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-geopriv-uncertainty/ballot/


No IPR declarations have been submitted directly on this I-D.

As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up.

Changes are expected over time. This version is dated 24 February 2012.

(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)?  Why
is this the proper type of RFC?  Is this type of RFC indicated in the
title page header?

## Standards Track - updates existing Standards Track RFCs 4119 and 5491

(2) The IESG approval announcement includes a Document Announcement
Write-Up. Please provide such a Document Announcement Write-Up. Recent
examples can be found in the "Action" announcements for approved
documents. The approval announcement contains the following sections:

Technical Summary

## This document describes improved semantics for expressing the uncertainty and confidence of a location object and specifies a new XML schema for describing these values within a PIDF-LO object per Standards Track RFC 4119.

Working Group Summary

## There were concerns over how a civic location might be
## "uncertain".  Text was added to clarify that the context
## was civic locations that have resulted from reverse-geocoding
## measured geodetic locations.

Document Quality

## The document has had good levels of working group review.

Personnel

## The document shepherd is Ray Bellis.
## The responsible AD is Alissa Cooper

(3) Briefly describe the review of this document that was performed by
the Document Shepherd.  If this version of the document is not ready
for publication, please explain why the document is being forwarded to
the IESG.

## I have checked the references and IANA actions
## I have validated the XML schema and XML examples.
## The document passes ID-nits tests

(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed? 

## No concerns

(5) Do portions of the document need review from a particular or from
broader perspective, e.g., security, operational complexity, AAA, DNS,
DHCP, XML, or internationalization? If so, describe the review that
took place.

## no additional reviews required that I am aware of

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.

## no specific concerns

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.

## Yes, both authors have confirmed that no IPR disclosures are required.

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.

## there are no IPR disclosures filed

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it? 

## The consensus is good, given the low level of participation in the WG.

(10) Has anyone threatened an appeal or otherwise indicated extreme
discontent? If so, please summarise the areas of conflict in separate
email messages to the Responsible Area Director. (It should be in a
separate email because this questionnaire is publicly available.)

## no appeals have been threatened

(11) Identify any ID nits the Document Shepherd has found in this
document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

## none found

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.

## the XML schema has been validated and examples checked
## for conformance thereof

(13) Have all references within this document been identified as
either normative or informative?

## Yes, and some upgraded to normative as a result of shepherd review

(14) Are there normative references to documents that are not ready for
advancement or are otherwise in an unclear state? If such normative
references exist, what is the plan for their completion?

## no such normative references exist

(15) Are there downward normative references references (see RFC 3967)?
If so, list these downward references to support the Area Director in
the Last Call procedure.

## none

(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.

## The document updates RFCs 3693, 4119 and 5491, and declares
## as such in the header and abstract (but not in the intro)
##
## For RFC 3693, see §2.2
## For RFCs 4119 and 5491 see the entirety of §3

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 5226).

## the document adds a new entry to each of the XML namespace
## registry and the XML Schema registry in apparent compliance with
## the guidelines in RFC 3688

(18) List any new IANA registries that require Expert Review for future
allocations. Provide any public guidance that the IESG would find
useful in selecting the IANA Experts for these new registries.

## none

(19) Describe reviews and automated checks performed by the Document
Shepherd to validate sections of the document written in a formal
language, such as XML code, BNF rules, MIB definitions, etc.

## The XML schema has been validated, and the XML examples within validated against that schema.

As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up.

Changes are expected over time. This version is dated 24 February 2012.

(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)?  Why
is this the proper type of RFC?  Is this type of RFC indicated in the
title page header?

## Standards Track - augments RFC 5139

(2) The IESG approval announcement includes a Document Announcement
Write-Up. Please provide such a Document Announcement Write-Up. Recent
examples can be found in the "Action" announcements for approved
documents. The approval announcement contains the following sections:

Technical Summary

## This document describes improved semantics for expressing the uncertainty and confidence of a location object and specifies a new XML schema for describing these values within a PIDF-LO object per Standards Track RFC 5139.

Working Group Summary

## There were concerns over how a civic location might be
## "uncertain".  Text was added to clarify that the context
## was civic locations that have resulted from reverse-geocoding
## measured geodetic locations.

Document Quality

## The document has had good levels of working group review.

Personnel

## The document shepherd is Ray Bellis.
## The responsible AD is Alissa Cooper

(3) Briefly describe the review of this document that was performed by
the Document Shepherd.  If this version of the document is not ready
for publication, please explain why the document is being forwarded to
the IESG.

## I have checked the references and IANA actions
## I have validated the XML schema and XML examples.
## The document passes ID-nits tests

(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed? 

## No concerns

(5) Do portions of the document need review from a particular or from
broader perspective, e.g., security, operational complexity, AAA, DNS,
DHCP, XML, or internationalization? If so, describe the review that
took place.

## no additional reviews required that I am aware of

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.

## no specific concerns

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.

## Yes, both authors have confirmed that no IPR disclosures are required.

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.

## there are no IPR disclosures filed

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it? 

## The consensus is good, given the low level of participation in the WG.

(10) Has anyone threatened an appeal or otherwise indicated extreme
discontent? If so, please summarise the areas of conflict in separate
email messages to the Responsible Area Director. (It should be in a
separate email because this questionnaire is publicly available.)

## no appeals have been threatened

(11) Identify any ID nits the Document Shepherd has found in this
document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

## none found

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.

## the XML schema has been validated and examples checked
## for conformance thereof

(13) Have all references within this document been identified as
either normative or informative?

## Yes, and some upgraded to normative as a result of shepherd review

(14) Are there normative references to documents that are not ready for
advancement or are otherwise in an unclear state? If such normative
references exist, what is the plan for their completion?

## no such normative references exist

(15) Are there downward normative references references (see RFC 3967)?
If so, list these downward references to support the Area Director in
the Last Call procedure.

## none

(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.

## none

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 5226).

## the document adds a new entry to each of the XML namespace
## registry and the XML Schema registry in apparent compliance with
## the guidelines in RFC 3688

(18) List any new IANA registries that require Expert Review for future
allocations. Provide any public guidance that the IESG would find
useful in selecting the IANA Experts for these new registries.

## none

(19) Describe reviews and automated checks performed by the Document
Shepherd to validate sections of the document written in a formal
language, such as XML code, BNF rules, MIB definitions, etc.

## The XML schema has been validated, and the XML examples within validated against that schema.

As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up.

Changes are expected over time. This version is dated 24 February 2012.

(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)?  Why
is this the proper type of RFC?  Is this type of RFC indicated in the
title page header?

## Standards Track - augments RFC 5139

(2) The IESG approval announcement includes a Document Announcement
Write-Up. Please provide such a Document Announcement Write-Up. Recent
examples can be found in the "Action" announcements for approved
documents. The approval announcement contains the following sections:

Technical Summary

## This document describes improved semantics for expressing the uncertainty and confidence of a location object and specifies a new XML schema for describing these values within a PIDF-LO object per Standards Track RFC 5139.

Working Group Summary

## There were concerns over how a civic location might be
## "uncertain".  Text was added to clarify that the context
## was civic locations that have resulted from reverse-geocoding
## measured geodetic locations.

Document Quality

## The document has had good levels of working group review.

Personnel

## The document shepherd is Ray Bellis.
## The responsible AD is Alissa Cooper

(3) Briefly describe the review of this document that was performed by
the Document Shepherd.  If this version of the document is not ready
for publication, please explain why the document is being forwarded to
the IESG.

## I have checked the references and IANA actions
## I have validated the XML schema and XML examples.
## The document passes ID-nits tests

(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed? 

## No concerns

(5) Do portions of the document need review from a particular or from
broader perspective, e.g., security, operational complexity, AAA, DNS,
DHCP, XML, or internationalization? If so, describe the review that
took place.

## no additional reviews required that I am aware of

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.

## no specific concerns

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.

## MT - yes,  AJW - requested, awaiting receipt

(8) Has an IPR disclosure been filed that references this document?
If so, summarize any WG discussion and conclusion regarding the IPR
disclosures.

## there are no IPR disclosures filed

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it? 

## The consensus is good, given the low level of participation in the WG.

(10) Has anyone threatened an appeal or otherwise indicated extreme
discontent? If so, please summarise the areas of conflict in separate
email messages to the Responsible Area Director. (It should be in a
separate email because this questionnaire is publicly available.)

## no appeals have been threatened

(11) Identify any ID nits the Document Shepherd has found in this
document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

## none found

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.

## the XML schema has been validated and examples checked
## for conformance thereof

(13) Have all references within this document been identified as
either normative or informative?

## Yes, and some upgraded to normative as a result of shepherd review

(14) Are there normative references to documents that are not ready for
advancement or are otherwise in an unclear state? If such normative
references exist, what is the plan for their completion?

## no such normative references exist

(15) Are there downward normative references references (see RFC 3967)?
If so, list these downward references to support the Area Director in
the Last Call procedure.

## none

(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.

## none

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 5226).

## the document adds a new entry to each of the XML namespace
## registry and the XML Schema registry in apparent compliance with
## the guidelines in RFC 3688

(18) List any new IANA registries that require Expert Review for future
allocations. Provide any public guidance that the IESG would find
useful in selecting the IANA Experts for these new registries.

## none

(19) Describe reviews and automated checks performed by the Document
Shepherd to validate sections of the document written in a formal
language, such as XML code, BNF rules, MIB definitions, etc.

## The XML schema has been validated, and the XML examples within validated against that schema.