Subject: [Geopriv] draft-ietf-geopriv-loc-filters-11

From: Hannes Tschofenig <[email-masked]>
Date: Sat, 27 Mar 2010 16:15:07 -0700

Hi Lars,

based on your feedback we changed the following aspects:

Discuss (2010-03-09)
Section 9.1., paragraph 2:
 >    [I-D.ietf-geopriv-arch]
 >               Barnes, R., Lepinski, M., Cooper, A., Morris, J.,
 >               Tschofenig, H., and H. Schulzrinne, "An Architecture for
 >               Location and Location Privacy in Internet Applications",
 >               draft-ietf-geopriv-arch-01 (work in progress),
 >               October 2009.

  DISCUSS: Downref: Normative reference to an Informational draft:
  draft-ietf-geopriv-arch (ref. 'I-D.ietf-geopriv-arch'). Didn't see it
  called out in the IETF LC.

Comment (2010-03-09)
Non-blocking comments:

[hannes] I guess we will need the normative reference. Although it only 
points to the terminology I think we cannot move it to the informative 
part.

Section 3.1., paragraph 1:
 >    The <moved> element MUST contain a value in meters indicates the
 >    minimum distance that the resource must have moved from the location
 >    of the resource since the last notification was sent in order to
 >    trigger this event.  Note that the condition could be met by a change
 >    in any axis including altitude.

  But surely not only by change along a single axis, right? (I think
  what you mean is that the length of the vector between the two points
  is longer than <moved>.)

We offer updated text in Section 3.1.

Section 5.2.3, paragraph 1:
 >    If the Target was previously outside the region, the notifier sends a
 >    notification when the Target's location is within the region with at
 >    least 50% confidence.  Similarly, when a Target starts within the
 >    region, a notification is sent when the Target's location moves
 >    outside the region with at least 50% confidence.

  Why 50%? Why not 30 or 70%? (Magic number.)

It is a magic number -- we have to provide some value. 50% seemed to be 
a reasonable value.

Section 5.2.3, paragraph 2:
 >    Note that having 50% confidence that the Target is inside the area
 >    does not correspond to 50% outside.  The confidence that the location
 >    is within the region, plus the confidence that the location is
 >    outside the region is limited to the confidence of the location.  The
 >    total confidence depends on the confidence in the location, which is
 >    always less than 100% (95% is recommended in [RFC5491]).  The benefit
 >    of this is that notifications are naturally limited: small movements
 >    at the borders of the region do not trigger notifications.

  Whether the last sentence is true depends entirely on how accurate the
  positioning is compared to the movement.

We clarified the sentence.

Section 9., paragraph 0:
 > 9.  References

  idnits reports several unused references, including normative ones.

Fixed.

Section 3.3., paragraph 5:
 >    In times where it is desireable to know if any one element of a list

  Nit: s/desireable/desirable/

Fixed.

Ciao
Hannes