16 Aug
2007
16 Aug
'07
10:53 a.m.
cherami(a)gmx.de wrote:
Hi,
I am student and new to the Presence Model und Protocols.
I have in my student project the following scenario:
So, one task in this project would be to figure out the details by
yourself, right? As a starting point, you should gather some
material about distinct presence protocols and learn how these
protocols work·
company A wants to develop a presence service PA. The
presence service
PA should get the data from the presence server PB of an other Company B
over the Internet. The Presence information of PA should be made
available in the Company A for different applications.
my question:
can PA poll or subscribe all changed/updated Presence Information from
PB regularly. Or it should request the Presence Information of each
Presentity individually?
Most "real" presence protocols such as SIP-based presence (sometimes
referred to as "SIMPLE") and XMPP at least allow for individual
subscriptions as well as so-called subscriber lists.
One of the problems with this kind of application is the overhead
from presence messages, especially when using SIP. Therefore, XMPP
might be a better choice for your specific application since it can
provide for confederations of presence servers over a more efficient
communication channel.
which Presence server can implement the presence
service PA.
SER could do this for SIP-based presence (including resource
subscription lists), ejabberd could be used for XMPP.
What should I do if PB uses another Protokoll?
You would have to use a protocol gateway. Look at the
presence-related SER documentation to learn how this works.
HTH,
Olaf