Subject: RE: [Simple] Re: [Geopriv] Individuals, hats and spheres

From: [email-masked]
Date: Wed, 10 Sep 2003 16:35:56 +0300

I did suggest Dimension. Also, how about Facet?

/Hisham

> -----Original Message-----
> From: ext Henning Schulzrinne [mailto:[email-masked]]
> Sent: Tuesday, September 09, 2003 6:15 PM
> To: John Schnizlein
> Cc: [email-masked]; [email-masked]
> Subject: Re: [Simple] Re: [Geopriv] Individuals, hats and spheres
> 
> 
> I myself am less than happy with the term sphere. "Role" has been 
> suggested and may be less overloaded, however, it doesn't quite work.
> 
> I would say that I play the role of 'father' or 'teacher', but I 
> wouldn't say that I'm in a work role or private role.
> 
> Amateur and professional sociologists may want to step in here...
> 
> John Schnizlein wrote:
> > My impression is that the spherical shape of the earth's geography
> > is an unintended analogy to the "spheres of interest" Henning meant.
> > This might be sufficient reason to change the word, but the concept
> > of many-to-many categories of individuals is important. Allowing
> > watchers in the same category to get my location is the concept.
> > 
> 
> 
> _______________________________________________
> Simple mailing list
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> https://www1.ietf.org/mailman/listinfo/simple
> 

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---

From: Henning Schulzrinne <[email-masked]>
Date: Wed, 10 Sep 2003 09:42:49 -0400

Facet, in particular, is being used (in the IETF, by John Klensin's 
drafts) in a completely generic way, describing any attribute of a resource.

---

From: Henning Schulzrinne <[email-masked]>
Date: Wed, 10 Sep 2003 09:42:49 -0400

---

From: Jonathan Rosenberg <[email-masked]>
Date: Fri, 12 Sep 2003 03:14:03 -0400

Facet has also been used already as a concept in the publication work 
in SIMPLE, and there it had a related function. It allowed a publisher 
to declare a presence document to be associated to a specific facet, 
and then specify watchers that were associated with the facet. The 
result was that different watchers could get different views of the 
presence data. Thats almost the same thing, but different in that 
"sphere" is saying something about the state of the presentity, and 
then use that to determine which information is distributed to 
different watchers.

Indeed, this begs the question of which approach is the desired 
approach for sphere. If its only use is to define a state which is 
then used to make authorization decisions at the presence server, 
there is no need to have any meaning for the value of sphere at all. I 
could publish a document with:

<sphere>1</sphere>

and have corresponding authorization rules which give out different 
information depending on whether sphere is 1 or 2.

Having enumerated values with defined meanings is useful if the 
information is also published to watchers, and I think that does make 
sense to do that. I frequently set my yahoo status to "working at 
home, call cell" to basically convey my "sphere" and the associated 
contact information for me when I am in that sphere (my cell).

If you add a presence status like this, it also makes sense to add 
corresponding capabilities in the authorization policies, which allow 
you to say "if presence element X has value Y, please do[n't] 
distribute presence element Z". XCAP-auth at the moment has no such 
capability. AS has been pointed out, such a capability would also be 
useful to make decisions based on other elements besides sphere.

Thanks,
Jonathan R.

Henning Schulzrinne wrote:

> Geopriv mailing list
> [email-masked]
> https://www1.ietf.org/mailman/listinfo/geopriv
> 

-- 
Jonathan D. Rosenberg, Ph.D.                600 Lanidex Plaza
Chief Technology Officer                    Parsippany, NJ 07054-2711
dynamicsoft
[email-masked]                     FAX:   (973) 952-5050
http://www.jdrosen.net                      PHONE: (973) 952-5000
http://www.dynamicsoft.com

---

From: Jonathan Rosenberg <[email-masked]>
Date: Fri, 12 Sep 2003 03:14:03 -0400

<sphere>1</sphere>

Thanks,
Jonathan R.

---

From: Ben Campbell <[email-masked]>
Date: Fri, 12 Sep 2003 11:23:21 -0500

Jonathan Rosenberg wrote:
> Facet has also been used already as a concept in the publication work in 
> SIMPLE, and there it had a related function. It allowed a publisher to 
> declare a presence document to be associated to a specific facet, and 
> then specify watchers that were associated with the facet. The result 
> was that different watchers could get different views of the presence 
> data. Thats almost the same thing, but different in that "sphere" is 
> saying something about the state of the presentity, and then use that to 
> determine which information is distributed to different watchers.
> 
> Indeed, this begs the question of which approach is the desired approach 
> for sphere. If its only use is to define a state which is then used to 
> make authorization decisions at the presence server, there is no need to 
> have any meaning for the value of sphere at all. I could publish a 
> document with:
> 
> <sphere>1</sphere>
> 

I was thinking the same thing. This makes the concept of sphere really 
become a concept of what authorization profile I want to have active at 
any given time. If we are willing to strip any other semantic meaning 
from sphere, then I would propose the term "profile" or 
"authorization-profile".

> sense to do that. I frequently set my yahoo status to "working at home, 
> call cell" to basically convey my "sphere" and the associated contact 
> information for me when I am in that sphere (my cell).

Doing this _does_ require some agreement between presentity and watcher 
as to what a given value means, i.e. a value of "home" is more useful 
than a value of "1". Or at least we would need to standardize the 
enumeration.  I don't think this agreement is necessary between 
presentity and presence agent.

> you to say "if presence element X has value Y, please do[n't] distribute 
> presence element Z". XCAP-auth at the moment has no such capability. AS 
> has been pointed out, such a capability would also be useful to make 
> decisions based on other elements besides sphere.
> 
> Thanks,
> Jonathan R.
>

---

From: Ben Campbell <[email-masked]>
Date: Fri, 12 Sep 2003 11:23:21 -0500

---

From: Henning Schulzrinne <[email-masked]>
Date: Fri, 12 Sep 2003 12:53:51 -0400

> from sphere, then I would propose the term "profile" or 

I agree that there is no need to have a fixed set of labels for that, 
unless you want to also convey this to watchers. This could occur, for 
example, if I want to tell my work buddies that I'm in private mode 
(implying that any attempt to contact me better be an emergency that 
can't wait until the next morning). Even in that case, one could argue 
that this is best handled by labels that I choose and that are 
meaningful to my life.

> presentity and presence agent.

I'm not sure it needs to be standardized, although suggesting a few 
standard terms ('work', 'off work', for example) may well be helpful and 
does not interfere with the ability to define tokens that make sense 
locally.

We have taken this approach for almost all the enumerations in RPID: 
there's a set of tokens that are enumerated in the document to reduce 
gratuitous variations ('work', 'at work', 'on company time', 'counting 
the days to retirement', 'watching the clock', 'slaving away', 'on the 
clock', etc.), while not constraining users to that list.

>> useful to make decisions based on other elements besides sphere.

The geopriv work (published and in-progress) allows some such matching, 
based on time and geographic location of the target/presentity. For 
simplicity, I suspect that only equality matches based on tokens should 
be supported, rather than generic expressions or, say, lists.

---

From: Henning Schulzrinne <[email-masked]>
Date: Fri, 12 Sep 2003 12:53:51 -0400

---

From: Jonathan Rosenberg <[email-masked]>
Date: Fri, 12 Sep 2003 15:04:36 -0400

Henning Schulzrinne wrote:

>> become a concept of what authorization profile I want to have active 
>> at any given time. If we are willing to strip any other semantic 
>> meaning from sphere, then I would propose the term "profile" or 
>> "authorization-profile".
> 
> 

If you want to communicate this to watchers, you need defined labels 
with clear semantics. Thats important for watchers that are automata, 
that wish to summarize, render, or do some kind of processing based on 
the information.

>> Doing this _does_ require some agreement between presentity and 
>> watcher as to what a given value means, i.e. a value of "home" is more 
>> useful than a value of "1". Or at least we would need to standardize 
>> the enumeration.  I don't think this agreement is necessary between 

See above - if we don't standardize them, the only thing you can do at 
a watcher is present them to the user, in which case you may as well 
use a note.

> clock', etc.), while not constraining users to that list.

Well, to be clear, it creates iana registries for those where new ones 
can be added.

> be supported, rather than generic expressions or, say, lists.

I'm not sure what you mean here - how do lists come into play?

-Jonathan R.

---

From: Jonathan Rosenberg <[email-masked]>
Date: Fri, 12 Sep 2003 15:04:36 -0400

-Jonathan R.

---

From: Henning Schulzrinne <[email-masked]>
Date: Fri, 12 Sep 2003 15:33:24 -0400

> that wish to summarize, render, or do some kind of processing based on 

No disagreement. I just think that in some cases, we can't anticipate 
the useful labels and so should allow for private-use labels. They may 
well be informally defined within a user community, e.g., within a group 
of friends or colleagues, just not registered with some central authority.

For example, in a different context, I think we discussed that a 
hospital may well define a set of activity labels such as "performing 
operation", "bedside", "on call", etc. These are neither IANA-registered 
nor complete note-like free-for-alls.

>> The geopriv work (published and in-progress) allows some such 
>> matching, based on time and geographic location of the 
>> target/presentity. For simplicity, I suspect that only equality 
>> matches based on tokens should be supported, rather than generic 
>> expressions or, say, lists.
> 
> 

One could imagine a restriction such as

"if parameter X has a set of values drawn from set {A,B,C}"

this can always be decomposed into multiple rules, so this adds no 
expressiveness, just reduces the number of rules, but makes the matching 
messier.

---

From: Henning Schulzrinne <[email-masked]>
Date: Fri, 12 Sep 2003 15:33:24 -0400

---

From: Paul Kyzivat <[email-masked]>
Date: Mon, 15 Sep 2003 10:07:37 -0400

> nor complete note-like free-for-alls.

Why isn't this orthogonal to the concept of sphere? The sphere could be 
an arbitrary tag shared between the publisher and presence server, but 
not communicated to subscribers.

The attribute that is communicated to the subscriber is simply some 
element in the doc carried by the notify. It could be an existing item 
(e.g. note), or if need be it could be something new.

	Paul

---

From: Paul Kyzivat <[email-masked]>
Date: Mon, 15 Sep 2003 10:07:37 -0400

Paul

---

From: Henning Schulzrinne <[email-masked]>
Date: Mon, 15 Sep 2003 10:10:20 -0400

> not communicated to subscribers.

I don't see why we need to distinguish PUBLISH tags and NOTIFY tags. I 
should have the ability to exclude or include any tag in NOTIFY, without 
some artificial distinction between tags.

---

From: Henning Schulzrinne <[email-masked]>
Date: Mon, 15 Sep 2003 10:10:20 -0400

---

From: Jonathan Rosenberg <[email-masked]>
Date: Wed, 17 Sep 2003 02:46:43 -0400

> of friends or colleagues, just not registered with some central authority.

Thats fine. There is precendent for processes where other namespaces 
can be used, and someone else can be the central point of definition 
for those namespaces. See rfc2506 for example.

> expressiveness, just reduces the number of rules, but makes the matching 

OK, makes sense.

Do we have any kind of consensus that this sphere is good to have, and 
that is is both published->presence server and presence server-> watcher?

-Jonathan R.

---

From: Jonathan Rosenberg <[email-masked]>
Date: Wed, 17 Sep 2003 02:46:43 -0400

OK, makes sense.

-Jonathan R.