[Serusers] Re: problem for using the latest pa module
klaus.mailinglists at pernau.at
Mon Feb 9 18:15:04 CET 2004
Thanks for the information. One of my students here at the university
tries to implement a system where you can watch mobile user running
around and call them by clicking on the moving point at the map - all
with SIP. Currently we produce the location information at the mobile
client (ipaq + xlite) by reading the GPS data from a bluetooth GPS receiver.
On the other side, we would like to have a Windows based client, which
uses the RTC API. So the idea was to include the GPS information into
the presence by using the "user-provided presence info" (like
"x=123;y=456" instead of "i'm at lunch and come back at 2:30").
Nevertheless, therefore it would be necessary that the RTC API accepts
the notficiations from ser.
The RTC api sends its notifieys as application/xpidf+xml, not as
application/cpim-pidf+xml. Is this the same format with a different
name? I tried to find the definition of them, but I found several
outdated drafts. I took a closer look at the drafts from the impp
working group, but for example i couldn't find the definition of the
<presentitiy> tag. Can you point me to a document which describes the
format used by the RTC. Btw: which format uses the sipc or other
commerical SIP-based IM applications?
I also found no description of adding the exact geographical location
into the presence information in a more generic way (not the workaround
described above). Have you ever thought of this (as the columns are
already defined in the database tables)? E.g. it could be a dedicated
tag or an attribute in the location tag.
Jamey Hicks wrote:
> Klaus Darilion wrote:
>> Hi Jamey!
>> Im interested in the presence agent module, especially in including
>> geographical user information into the presence data.
>> What is the body type of the publication/notifications? Is it XML based
>> presence like used by Windows Messenger and Kphone? Is this format
>> defined somewhere? Is this the same as this old draft?
>> The presentity table includes x and y colums? Are these to represent the
>> geographical location of the publisher?
> Hi Klaus,
> The body type is application/cpim-pidf+xml with a couple extensions
> modeled on geopriv and civil location. The same body type is accepted
> by the code that handles PUBLISH and updates the database. The NOTIFY
> messages are generated from that. We have an 802.11 location tracking
> system that generates PUBLISH messages that include site, floor, room,
> x, y and radius of the position estimate. Our location tracking service
> yields roughly office-level resolution for the two floors of our
> building that we occupy. The position data is for the client device
> from which a user is registered. We also have PHP code for a presence
> portal that lets users update their location manually if no location
> service is available or if they wish to override the location provided
> by the location service.
> The presence agent still needs some work -- it currently allows anyone
> to subscribe. I have mostly coded support for the watcherinfo event
> package and for xcap access to presence-lists, so that users can be
> notified when a new person requests to subscribe to their presence info
> and so that users can use xcap to authorize/deny those requests. I have
> been working with Xiaotao Wu at Columbia to debug that against the sipc
> user agent and I've been adding code to linphone. It would be great if
> someone wants to add similar support to kphone. I may get to kphone but
> I have a lot on my plate right now.
> The other thing that the presence agent should have with respect to
> physical location is a way for a user to specify the resolution of the
> location information to be shared with other users. For example, I
> might want to let people know I'm on the 12th floor here but not which
> office I'm in.
> Another problem with the presence agent is that Windows Messenger does
> not accept the NOTIFY messages, so none of your contacts looks to be
> online. I'm not interested in supporting a UA that does not support the
> internet draft standards but if minor tweaks would make this work that
> would be OK.
> The final issue that comes to mind with the PA is that it is set up to
> aggregate presence for all user agents. It handles SUBSCRIBE and
> PUBLISH, and it generates NOTIFY. It gets basic online/offline status
> from the usrloc module but depends on the UA or other presence agent to
> PUBLISH more detailed information.
> I hope this is helpful. I am planning to write a document that outlines
> how this works and what is needed from UA's. I imagine that review and
> revision of that document will lead to changes in the PA implementation
> to make the whole system work better.
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> serusers at lists.iptel.org
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