Sorry to hear this really negative news on open-source Kamailio.
I want to share the following two good articles with you. Both articles shed light on the positive impact of building with SIP.
The 1st good article "H.323 and SIP Becoming Legacy. XMPP and JS are the Future"
April 12, 2012
The 12 comments for the article are also worth reading.
http://bloggeek.me/h323-sip-xmpp-js/ The 2nd good article "SIP vs XMPP or SIP and XMPP?" compares the 2 most popular signaling protocols - SIP and XMPP.
November 09, 2009
http://p2p-sip.blogspot.ca/2009/11/sip-vs-xmpp-or-sip-and-xmpp.html Due to its popularity, SIP faces with overload issue recently.
Build-in overload mechanism cannot prevent overload effectively. Therefore, IETF SIP Overload Control (soc) Working Group works on IETF RFC "SIP Overload Control" currently.
http://tools.ietf.org/html/draft-ietf-soc-overload-control-12 IETF SIP Overload Control discussion archives
http://www.ietf.org/mail-archive/web/sip-overload/current/threads.html#00874 We have published a survey on SIP overload control algorithms (including IETF RFC "SIP Overload Control").
"
A Comparative Study of SIP Overload Control Algorithms"http://www.researchgate.net/publication/231609451_A_Comparative_Study_of_SIP_Overload_Control_Algorithmshttp://arxiv.org/abs/1210.1505http://www.igi-global.com/chapter/comparative-study-sip-overload-control/67496 We have also used control theorectic approaches to model the interactions between an overloaded SIP server and its upstream servers as a feedback control system in two different scenarios - redundant retransmission ratio control and round trip delay control (IEEE Globecom 2010 and ICC 2011).
"Mitigating SIP Overload Using a Control-Theoretic Approach" IEEE Globecom 2010
http://www.researchgate.net/publication/221284946_Mitigating_SIP_Overload_Using_a_Control-Theoretic_Approachhttp://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5683124&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5683124 Implementation of implicit SIP overload control in the real system
"An Efficient Earthquake Early Warning Message Delivery Algorithm Using an in Time Control-Theoretic Approach"
http://link.springer.com/chapter/10.1007%2F978-3-642-23641-9_15#
http://www.ipv6.org.tw/docu/elearning8_2011/1010004798p_3-7.pdf "Design Of A PI Rate Controller for Mitigating SIP Overload" IEEE ICC 2011
http://www.researchgate.net/publication/224249824_Design_of_a_PI_Rate_Controller_for_Mitigating_SIP_Overloadhttp://features.rr.com/article/01vBgtc8TR17z?q=Skypehttp://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5963029&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5963029 Best regards,
> On Mar 31, 2013 6:33 PM, "Alex Balashov" <
abalas...@evaristesys.com> wrote:
> For immediate release:
>
> ATLANTA, GA (1 April 2013)--Evariste Systems LLC, an Atlanta-based
> consultancy specialising in Kamailio-based VoIP infrastructure solutions
> for the ITSP and CLEC market, has announced that beginning in the second
> quarter of 2013, it will be abandoning its Kamailio-based technology
> portfolio to focus on its new role as a preferred VAR (Value Added
> Reseller) for Acme Packet (NASDAQ:APKT).
>
> "It is with a heavy heart that we abandon five years of Kamailio-oriented
> work and the Canonical SIP Routing Platform product derived from it,"
> said Alex Balashov, the principal of the company.