1. Dynamic Feature Extensions to the Presence Information Data Format Location Object (PIDF-LO) draft-singh-geopriv-pidf-lo-dynamic-00.txt
Vishal K. Singh
Henning Schulzrinne
Hannes Tschofenig
IETF 67, San Diego

2. Requirements and Use Cases
Mechanism to indicate temporal features of entities
Mechanism to track location of moving objects
Use cases:
location tracking
fleet management
monitoring
safety of personnel
Extends RFC 4119 with temporal feature elements

3. Dynamic Feature Elements
Based on GML’s dynamicFeature.xsd
Speed
Measure of the rate of motion
Bearing
Direction: compass point (e.g., "N", "NNE")
type gml:DirectionPropertyType
Acceleration
The rate (usually rapid) at which something happens
Elevation
The height of an entity above a reference level; altitude

4. Example xmlns:temp="urn:ietf:params:xml:ns:temporal1“
<presence xmlns="urn:ietf:params:xml:ns:pidf“
xmlns:gp=“urn:ietf:params:xml:ns:pidf:geopriv10”
xmlns:temp="urn:ietf:params:xml:ns:temporal1“
<tuple id="sg89ae">
<status>
<gp:geopriv>
<gp:location-info>
<gml:location> ………… </gml:location>
<temp:speed uom="#kph">12</temp:speed>
<temp:bearing>
<temp:CompassPoint>SE</temp:CompassPoint> </temp:bearing>
</gp:location-info>
<gp:usage-rules>
………… ………… …………
</gp:usage-rules>
</gp:geopriv>
</status>
<timestamp> T20:57:29Z</timestamp>
</tuple>
</presence>

5. Protocol Behavior Indicating the use of dynamic feature in PIDF-LO
Indicating units of measure
GML units to measure parameters

6. Multiple Moving Object Elements
Watchers may request to receive multiple location vector objects together
Use of <timed-status> to transfer multiple location vector objects
<tuple>
<status>
<gp:geopriv> </gp:geopriv>
</status>
<timestamp>.....</timestamp>
<timed-status from="some time" until="some time">
<gp:geopriv> </gp:geopriv>
<gp:geopriv> </gp:geopriv>
</timed-status>
</tuple>
<tuple> </tuple>

7. Alternatives Considered
Could use <MovingObjectStatus> or its parent element <track> from GML’s dynamicFeature.xsd
But…
Backward compatibility problems OR
<location> appears twice
tuple 1
status
geopriv 1
location-info movingobjectstatus
location
speed location-info geopriv 2
old system won’t find <location>
duplicate <location> - mandatory below <movingobjectstatus>
tuple 1
status
geopriv 1
location-info location movingobjectstatus
location
speed geopriv 2

8. Open Issues
How does watcher indicate support of dynamic feature in PIDF-LO?
Proposals:
list supported namespaces
Accept: application/pidf+xml; supported="urn:ietf:params:xml:ns:temporal1"
register a token for each (set of) namespaces
Accept: application/pidf+xml; supported="geopriv-temporal-features“
watcher filter

9. Next Steps Adopt this as WG draft Submit a new version
Close the open issues
IANA considerations
Revise the text