1. B. ROSEN, M. THOMSON, D. STANLEY, G. BAJKO, A. THOMSON, S. MCCANN draft-thomson-geopriv-relative- location-00

2. This draft Combines two previous drafts on how to represent interior location (the “Stanley” draft on offset from a civic and the “Thomson” draft on offset from a geo) Extends a PIDF-LO to have an offset represented by a geoshape Also defines a “map” element for a floorplan, database or other secondary reference data to enable display of “you are here” or “go there”, etc. Defines TLV representations for the offset shapes

3. Example <presence xmlns="urn:ietf:params:xml:ns:pidf" xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model" xmlns:gp="urn:ietf:params:xml:ns:pidf:geopriv10" xmlns:ca="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" xmlns:gml="http://www.opengis.net/gml" xmlns:gs="http://www.opengis.net/pidflo/1.0" entity="pres:ness@example.com"> AU NSW Wollongong North Wollongong Flinders Street 123 Front <gml:Point xmlns:gml="http://www.opengis.net/gml" srsName="--TBD--"> 100 50 GPS mac:1234567890ab 2007-06-22T20:57:29Z

4. The reference point Is a location information (that is, a geo or civic, as we currently define it) There is some author disagreement on how to represent the reference

5. The offset Defined geoshapes  Point  Circle/Sphere  Ellipse/Ellipsoid  Polygon/Prism Contained in a element in CRS is an (optional) angle in degrees from North, units of meters and uses the reference as the datum

6. The “Map” URI to some object: could be an image, could be a data structure MIME type to know what the object is Can include Angle, Scale and Offset to define map CRS

7. TLVs TLV definitions for the shapes that define the offset are provided in the draft New registry for the types that are explicitly non conflicting with 4776 (CAtypes) Could combine the reference using 4776 types with the offset using these types to get a relative offset, but this draft doesn’t define the details of how you do that

8. Open Issue: Representing the Reference The current draft just has the reference as a civicAddress or gml in The offset is a new in This means if you don’t understand you take the reference as the location Some authors think this is wrong and if you don’t understand the extension, you should get no location If the offset can be very large, this could be a problem