[Olsr-dev] First release of IP Autoconfig daemon (PAA)

[Roar Bjørgum Rotvik]

Hannes Gredler wrote:
> hi roar, andreas,

Thanks for your comments, I will try to answer them below.

> this looks good - many thanks - i have one nit wrt to licencing.
> the paa extensions are licensed as GPLv2 where olsrd is licensed
> to BSD. it it my understanding that this is not possible as you
> cannot link GPLv2 to any non GPLv2 object.

PAA consists of two parts:
1) Standalone PAA daemon (released code, GPLv3 license)
2) PAA-plugin for olsr (mainly flooding messages from PAA-daemon to the ad hoc network and 
back) (not released code yet, BSD licensed).

The standalone PAA daemon is for now licensed under GPLv3.
The olsr plugin part of PAA is to be licensed under BSD.
But the PAA daemon and the paa-plugin is not linked at all.

They communicate using IPC (in this case UDP packets between two (spam-protected)). 
Therefore there is no linking and I don't see a problem here. You may even skip the 
paa-plugin+olsr part and just use some other flooding mechanism (multicast or something) 
together with PAA daemon. They are two separate modules currently communicating over the 
network.

> Q: would it be ok for you to change the license to something less
> restrictive ?

See below.

> BSD would be ideal, as it would also allow us to e.g. move in PAA code
> from the plugin to the core of the olsrd.
> LGPL would at least allow it to get included/linked as a plugin, however
> would prohibit insourcing into the core tree.

Reading your statement "move in PAA code from the plugin to the core of the olsrd" makes 
me wonder if you have understood the two parts in PAA as described in the start of this 
email. The paa-plugin may be moved to the olsr core, but I don't see the reason for it.

I'm not sure that moving the PAA daemon into olsr would bee a good idea.
Some issues:
* Today PAA need to acquire an IP address _before_ starting olsr, since olsr in the past 
did not like changes/addition of IP-addresses on one of it's interfaces.
I don't know if the current olsr would like for a plugin to change/add IP address on a 
running interface?
* If olsr is still single-threaded it could hurt routing performance to implement even 
more processing in the single-thread event loop in olsr.
* PAA daemon uses a thread (to generate FORWARD_REQ messages). I don't know if you would 
like threads inside olsr.

My priority list is as this for now:
* Add copyright and license to the paa-plugin source code
* Release paa-plugin source code (hope to release it during next week)
* Fix up paa-plugin to work against current olsr (currently it is coded to work against 
uolsr-0.4.3).
* Test and make PAA work, also in some bigger networks

Regarding relicense the PAA daemon to BSD and incorporate it into olsr; I'm not against 
the idea but someone need to convince me that it is smart (and I may need management 
approval) :)

But first I would like to make it work as it is against current olsr release..

-- 
Roar Bjørgum Rotvik