Hi,
I need some advices about a design issue. I'm trying to figure out how to manage my presence information notifications, using RFC 3856.
I have a situation in which end-to-end presence management wouldn't be suitable.
Still I'm wondering if server based presence management is a good idea. My thought is that it present a scalability issue. The point is that having the presence server would have to handle every single SUBSCRIBE & PUBLISH request then sends NOTIFY to every watchers.
Is it an efficient way to handle presence in a network with hundreds online users, everyone having tens of contact on their list.
Thank you for your comments
Luba Vincent
Hi Vincent,
skipping the fact that the pa module from OpenSER is still not mature and the presence encoding is not compatible between all SIP UA, in order to distribute the presence related traffic you may use several presence openser server; Based on static rules, the proxy may distribute the traffic among the presence servers - static load-balancing. Like the present of users from A to E will be kept on server1, for users from F to J will be kept on server2 and so on.....
just an idea....
regards, bogdan
Vincent Luba wrote:
Hi,
I need some advices about a design issue. I'm trying to figure out how to manage my presence information notifications, using RFC 3856.
I have a situation in which end-to-end presence management wouldn't be suitable.
Still I'm wondering if server based presence management is a good idea. My thought is that it present a scalability issue. The point is that having the presence server would have to handle every single SUBSCRIBE & PUBLISH request then sends NOTIFY to every watchers.
Is it an efficient way to handle presence in a network with hundreds online users, everyone having tens of contact on their list.
Thank you for your comments
Luba Vincent
Users mailing list Users@openser.org http://openser.org/cgi-bin/mailman/listinfo/users
Vincent Luba wrote:
Hi,
I need some advices about a design issue. I'm trying to figure out how to manage my presence information notifications, using RFC 3856.
I have a situation in which end-to-end presence management wouldn't be suitable.
Still I'm wondering if server based presence management is a good idea. My thought is that it present a scalability issue.
The overall number of messages sent/received will be lower when using serverbased presence. Imagine a SIP client with modem connectin and 50 users on its buddylist:
end2end: 50xNOTIFY to the SIP proxy + 50xNOTIFY to the SIP clients + 50 responses (200 ok) + 50 responses
server based: 1xPUBLISH + 50xNOTIFY to the SIP clients +1 responses (200 ok) + 50 responses
This will lower the traffic on the SIP proxy and on the UAC side.
But of course, a presence server needs CPU power and has to store the presence locally in a database. Thus, as you see, this is a trade of.
simple server and high network traffic vs complicated server and low traffic and centralized features (buddy list...)
Additionally, you also have to consider SIP implementations. There are not thousands of SIP clients which supports all presence modes. Some clients supports end2end, some clients support server based. The same with SIP proxies.
Conlusion. Get some clients and implement both scenarios and find the one which fits your needs.
klaus
The point is that having the presence server would have to handle every single SUBSCRIBE & PUBLISH request then sends NOTIFY to every watchers.
Is it an efficient way to handle presence in a network with hundreds online users, everyone having tens of contact on their list.
Thank you for your comments
Luba Vincent
Serusers mailing list Serusers@iptel.org http://mail.iptel.org/mailman/listinfo/serusers
-----Message d'origine----- De : Klaus Darilion [mailto:klaus.mailinglists@pernau.at] Envoyé : vendredi 9 septembre 2005 10:29 À : Vincent Luba Cc : sip-implementors@cs.columbia.edu; serusers@iptel.org; users@openser.org Objet : Re: [Serusers] Scalability in presence notification
simple server and high network traffic vs complicated server and low traffic and centralized features (buddy list...)
You're right in my case I'll have to use server based. I've performed some load tests with SER and noticed that PUBLISH & SUBSCRIBE requests uses lot of CPU power while NOTIFY request are not that cpu intensive.
Additionally, you also have to consider SIP implementations. There are not thousands of SIP clients which supports all presence modes. Some clients supports end2end, some clients support server based. The same with SIP proxies.
Conlusion. Get some clients and implement both scenarios and find the one which fits your needs.
I'll be using a GnomeMeeting mod client and server based presence should be enabled.
Thank you for you information,
Vincent
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Bogdan-Andrei Iancu -
Klaus Darilion -
Vincent Luba