[Xorp-users] Question regarding GPL license

[张东亚]

Hi lists,
  Recently I am interest in a company named pica8 which stated they
want to build an open source switch platform.

  I read their blog link regarding license issue
(http://pica8.org/blogs/?p=137), they said they will choose the
dual-license model as following:

Open Source License

We decide to use MySQL license model for PicOS, which is a Dual
license model, including both GPLv2 and commercial licenses

GPLv2 licensed for the developer community
OEM/ISV/VAR that does not wish to open source under GPLv2 must obtain
a commercial license from Pica8

What is Pica8′s dual license model?

Pica8 makes its PicOS available under both the GPL and a commercial
license. As a result, developers who use or distribute open source
applications under the GPL can use the GPL-licensed Pica8 software,
and OEMs, ISVs and VARs that do not want to combine or distribute the
Pica8 software with their own commercial software under a GPL license
can purchase a commercial license.

  However, according to the GPL license FAQ:

  Q: If I add a module to a GPL-covered program, do I have to use the
GPL as the license for my module?
  A: The GPL says that the whole combined program has to be released
under the GPL. So your module has to be available for use under the
GPL.
       But you can give additional permission for the use of your
code. You can, if you wish, release your program under a license which
is more lax than the GPL but compatible with the GPL. The license list
page gives a partial list of GPL-compatible licenses.

  I think it's not proper that they can release their software under a
commercial license, what's your opinion about this dula-license model?

  Thanks a lot.

Regards,

Dongya ZHang