[kea-dev] Licensing of Yang models

[Tomek Mrugalski]

On 07.01.2022 15:53, Roman Mashak wrote:
> KEA Dhcp comes with Netconf support and a handful of Yang modules in
> https://gitlab.isc.org/isc-projects/kea/-/tree/master/src/share/yang/modules
All my responses below apply to kea YANG modules.

There's also a handful of IETF modules. IIRC Kea can support
ietf-dhcpv6-server to some degree. They are coming from an earlier
version of the IETF draft. Link to the latest is:
https://datatracker.ietf.org/doc/html/draft-ietf-dhc-dhcpv6-yang-24.
According to its Copyright Notice on the first page, they're distributed
under Simplified BSD License with the copyright owner being IETF.

> However, I could not find under what license the Yang modules are
> distributed. Is it the same as the KEA-Dhcp package (i.e. Mozilla
> Public License v2.0)?
Yes. MPL 2.0.

> What happens if I modify the shipped Yang modules, 
Github has a good quick overview of the MPL2.0 license:
https://github.com/isc-projects/stork/blob/master/LICENSE
(Kea's LICENSE file has some extra text on it, so gitlab doesn't
recognize it, hence the link to Stork).

If in doubt, please do read the MPL 2.0 text. It's not that long.
In particular, see Sections 3.1 and 3.2.

> or add a new one,
> am I supposed to return the changes in the open source community?
MPL is file-based license. If you add a new file, it's up to you to
decide the license.

Obviously, this is not a legal advice. I'm not a lawyer.

Out of curiosity, what did you change or added in the YANG modules? We
gotten very little feedback for NETCONF implementation. Either it's
perfect or very few people use it. I'm a bit too old to believe in the
former ;)

Tomek