[Kamailio-Devel] Kamailio for commerical use

[Henning Westerholt]

On Tuesday 03 February 2009, Johansson Olle E wrote:
> [..]
> The question here is how your product integrates with Kamailio. If you
> write your own modules that link to Kamailio through the binary API,
> then they will be licensed by GPL. If you use the MI or just SIP, they
> propably won't.
>
> I realized that we have other interfaces, the SEAS interface. Maybe
> it's time for the developer team to clarify their view of the license
> situation with MI and SEAS.

Hi Olle, Hi Kavita,

i've got the impression that one purpose of the SEAS interface is to 
interconnect to closed source applications with a binary network interface. 
This is more or less similar to other protocols like SIP, thus i think this 
is not a problem. With the MI interface its a bit more unclear. This is used 
as normal user interface, but also to interconnect proprietary software to 
kamailio.

Lets compare to another project that also have this problem, e.g. the linux 
kernel. They provide a certain set of interface to connect to closed source 
modules too. Even if many developer don't really like this [2], its still 
allowed, even its probably "borderline legal" [1]. I agree that it would be 
better to have some clear wording in our licence, like suggested in [3], but 
for the moment this is not available.

So as conclusion, i also think that communication of proprietary software with 
the kamailio MI_FIFO interface over a fifo file, UDP socket or XMLRPC calls 
would be ok. But keep in mind that i'm not a lawyer, to get a definitive 
answer (which also depends on your special usage scenario) you should talk to 
one.

Cheers,

Henning



[1] http://www.linuxjournal.com/article/6152
[2] http://lwn.net/Articles/287056/
[3] http://www.gnu.org/licenses/gpl-faq.html#LinkingOverControlledInterface