Data%20model%20and%20RPID

About This Presentation

Title:

Data%20model%20and%20RPID

Description:

PA may not be aware ... May want to delegate filtering and element-level ... Delegate to (human) watcher, possibly with other context information ... – PowerPoint PPT presentation

Number of Views:18

Avg rating:3.0/5.0

Slides: 17

Provided by: softa

Category:

more less

Transcript and Presenter's Notes

Title: Data%20model%20and%20RPID

1
Data model and RPID

Henning Schulzrinne
Columbia University

2
Requirements

Allow for uncertainty
Allow for smart watchers (and dumb PAs)
Allow different composition policies
Support forward compatibility
Support lossless Pas
Well-defined meaning

3
Can we build forward-compatible PAs and composers?

PA may not be aware of XML schema details
assume only knows drafts of today lttuplegt,
ltservicegt, ltdevicegt
e.g., imagine pre-lttimed-statusgt implementation
can only keep one element (most recent)
i.e., forces information loss
May want to delegate filtering and element-level
manipulation to other entity

4
Multi-stage architecture
PUBLISH (only to mobile.com)
mobile.com PA
personal.org
SUBSCRIBE NOTIFY
utility.com PA
5
Example lttimed-statusgt

lttstimed-statusfrom"2003-08-15T102000.000-05
00" until"2003-08-22T193000.000-0500"gt
ltbasicgtclosedlt/basicgtlt/tstimed-statusgt
How do you compose multiple sources without
information loss?
Adding layers doesnt help unless it is done now
ltpersongt ltviewgt lt/viewgtlt/persongt

6
Model Minimal composer

Agreement dont specify composer detail, but
some minimal model(s)
Two models proposed
smart combines contradictory information
(pivoting), removing
requires some understanding of XML schema
dumb concatenates published elements within
ltpresentitygt
requires only knowing lttuplegt, ltpersongt, ltdevicegt
No need to exhaustive, but worried about
excluding particular

7
Model tuple identification

Agreement every tuple has a presentity-unique
identifier
All composition policies MUST replace ltgt with the
same ID
Disagreement are there other unique,
mandatory-to-replace identifiers
Proposal no, but any composition policy MAY use
anything for pivoting, including URIs

8
Model source meta-data

Later, but need to plan ahead
Meta data
source of information
type of entry (measured vs. manual)
trustworthiness
update frequency,

Affected by ltpersongt decision and composition
policy

9
Model source meta-data

Option 1 (multiple)

Option 2 (one ltpersongt)

ltpersongt ltsourcegts1lt/sourcegtlt/persongtltpersongt
ltsourcegts2lt/sourcegtlt/persongt
ltpersongt ltmood sources1gtlthappy/gtlt/moodgt
ltmood sources2gtltsad/gtlt/moodgt lt/persongt ltperson
gt ltsourcegt ltmoodgtlthappy/gtlt/moodgt
lt/sourcegt ltsourcegt ltmoodgtltsad/gtlt/moodgt
lt/sourcegt lt/persongt
10
Notes on extensions

Meta data is instance of general extensibility
problem
Option 2a may violate (RPID or similar) schema
Option 2b is not backward-compatible even though
ltsourcegt is optional information
but would be acceptable if defined as part of
data model now (but would require more
complicated composer)

11
Model ltpersongt uncertainty

Multiple sources of data for person data
calendar
manual entry
body sensors
Composer may not have any reliable way to
identify correct information
Delegate to (human) watcher, possibly with other
context information

12
ltspheregt

For published variables that serve as rule
selection input into privacy policy, need to
determine which of conflicting variables is used
Motivation composition (output) and selection
are logically separate
Proposal allow separate algorithm
e.g., ordering (work gt play)
most recent

13
RPID Changes

Alignment with data model
ltidlegt ? ltuser-inputgt
lttimezonegt
To do fix schema and examples

14
RPID ltspheregt

Sphere part of my life (set of people)
Im wearing my parent hat right now
Some differences of understandings
information to be delivered when Im in
work/play/travel mode
more similar to ltclassgt
Im in IETF sphere right now
in PUBLISH ? may be used by composer to select
appropriate elements or receivers
Original intent was (2)
Agreement?

15
RPID Enumerations