Yes, you can use kamailio to provide VoIP backend -- all free of charge and without constraints.

As Fred pointed in another email, kamailio is GPLv2 and the main restriction of that license is to distribute the sources to anyone that gets the binaries from you. If you install kamailio on your servers, then you do not distribute it and it is no need to give away the source code. That means, even if you have a module that you develop and you use it in your servers, then you don't need to give away its sources. If you simply use stock Kamailio, then the sources are already available for the public.

That is rather basic description, if you are not sure about what you are doing with Kamailio, then as Fred suggested, it is better to consult a lawyer.

Cheers,
Daniel

On 15/06/15 18:09, Alexandru Covalschi wrote:
Maybe it may be an offtopic, but I'm not really into legal issues - so I'm sorry if this message is not fully related to this mailing list.

Can I use Kamailio to provide VoIP backend for kind of CRM system in case of SaaS?

---
Alexandru Covalschi
ABRISS-Solutions
VoIP engineer and system administrator
phone: +37367398493
web: http://abs-telecom.com/


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