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Hello Telepathy people!<br>
<br>
I'm developing an XPMN media server called Pontarius. I'm currently
looking into how XPMN could be integrated with Telepathy. You can
read about Pontarius at <a class="moz-txt-link-freetext" href="http://www.pontarius.org/">http://www.pontarius.org/</a>.<br>
<br>
First off, let me clarify some XPMN terms:<br>
<br>
<b>XPMN:</b> Stands for Extended Personal Media Network and is a
decentralized media network software architecture. It allows
extended media networks to communicate seamlessly and addresses
service discovery (allowing devices to find and identify each other
and their capabilities), security (access control, encryption) and
extensibility (making it easy to extend for future use cases), all
while being easy to set up and use. All-in-all, it's an extremely
powerful way to arrange your media networks.<br>
<br>
<b>Extended media network:</b> An overlay network consisting (XPMN)
devices from one or more networks, such as home networks. One
problem that XPMN solves is that devices are able to communicate
(over for example Internet) even though they belong to different
subnetworks.<br>
<br>
<b>Service:</b> A specific task or set of tasks that devices may be
capable of fulfilling. One example could be a TV playback and
recording service.<br>
<br>
<b>Device:</b> A logical entity in the extended media network. It
does not have to be a physical device; one physical device can
contain multiple (XPMN) devices. Devices are often bound to a
specific action (such as controlling media playback). A device may
be a controller, a service provider, or both.<br>
<br>
<b>Controller:</b> A device controlling one or more services.
Controllers can also be service providers. An example of a
controller could be a smartphone application that can act as a
remote control for a media player service, allowing the user to
play/pause, change the volume, etc.<br>
<br>
<b>Service provider:</b> A device providing one or more services.
Service providers can also be controllers.<br>
<br>
<b>Profile:</b> A profile is an extension on top of the XPMN
architecture. It is a specification that describes a service and
includes the communication protocol used between controllers and
service providers. There can be many implementations of any given
profile, and they should be seamlessly inter-operable.<br>
<br>
A XPMN device is basically a connected XMPP account. A directory
service could be using the full Jabber ID
<a class="moz-txt-link-abbreviated" href="mailto:sprint3@test.pontarius.org/pontarius-directory">sprint3@test.pontarius.org/pontarius-directory</a>. XPMN devices
communicate by exchanging general IQ get/set/result messages as well
as a small subset of the pubsub spec (like subscriptions, events and
items requests). Service discovery capabilities also play a part.
The mechanics for this is the same for every profile. See The Status
and Variable Event Mechanism at <a
href="http://www.pontarius.org/test/0-1-alpha-2/">http://www.pontarius.org/test/0-1-alpha-2/</a>
for a brief (and incomplete) example of what it could look like.<br>
<br>
Every XPMN profile has a specialized API for the job that it's
doing, and they all use the above mentioned methods to do their job.
One simple profile could talk to a media player service to do things
like start and stop playback (think remote control), while another
profile can negotiate and download some data over a Jingle and
SOCKS5 connection from some kind of transfer service. The external
API for these profiles should be made as simple as possible, and the
profile should hide the "core" XPMN module (from the previous
paragraph) from the third party developer. He should probably only
know about the TpAccount he want to connect with, and the full JID
of the service he wants to talk to. He would most likely be
developing a Telepathy client.<br>
<br>
I don't really know where the "core" XPMN code and the
profile-specific (remote control, data transfer) code should go,
what it should be (Telepathy channels?) and how they should
communicate. What role could Gabble sidecars play here?<br>
<br>
Any ideas, comments or suggestions would be very appreciated!<br>
<br>
You can read more in-depth details about XPMN in Dirk Meyer's thesis
at <a class="moz-txt-link-freetext" href="http://elib.suub.uni-bremen.de/diss/docs/00011878.pdf">http://elib.suub.uni-bremen.de/diss/docs/00011878.pdf</a>. Also feel
free to ask questions to this mailing-list or to me directly. :-)<br>
<br>
Thanks!<br>
<br>
Warm regards,<br>
Jon Kristensen<br>
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