Licensing question.

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Asterisk Users 5 Comments


I have found next paragraph in Licence file(source root)
“Digium, Inc. (formerly Linux Support Services) holds copyright
and/or sufficient licenses to all components of the Asterisk
package, and therefore can grant, at its sole discretion, the ability
for companies, individuals, or organizations to create proprietary or
Open Source (even if not GPL) modules which may be dynamically linked at
runtime with the portions of Asterisk which fall under our
copyright/license umbrella, or are distributed under more flexible
licenses than GPL.”

What does it mean? Does it mean I can write non-GPL modules(BSD, MIT,
etc)? Can I build my modules in common asterisk source tree(i.e. using
LOCAL_MOD_SUBDIRS=”my_mod_subdirs_list” make ) or must use separate
tree? If so, then since Asterisk core does not accepts anything except
AST_MODULE_INFO(ASTERISK_GPL_KEY, ….) what I should do here?

5 thoughts on - Licensing question.

  • Asking for people on this list to tell you what ‘this means’ is like
    asking people on this list to tell you what is wrong with you if you
    have a headache and a fever; you will get answers, but they won’t be as
    useful as if you asked an expert in that field of inquiry 🙂

    In spite of that, I’ll give you Digium’s interpretation of what that
    paragraph means and attempt to answer your questions. Since Digium is
    the ‘licensor’ in this equation, our opinion certainly carries some
    weight, but you should consult with your own legal counsel in order to
    determine whether the actions you wish to take are compatible with the
    license terms or not.

    The paragraph you quoted above doesn’t directly grant you any rights at
    all; it is only a statement that Digium can, and does, grant third
    parties the ability to produce and distribute works that could be
    classified as ‘derivative works’ of Asterisk without being subject to
    the provisions of the GPL version 2 (as they would otherwise be, since
    most people receive Asterisk under that license). If you have a need for
    such a license, you should contact Digium to inquire about it.

    As far as your other questions go, they are fairly vague, but I can
    attempt to answer them:

    * The GPLv2 places no restrictions on what you can ‘write’, it only
    places restrictions on your distribution of things that you write that
    could be considered ‘derivative works’ of a GPLv2-covered work (in this
    case, Asterisk). If you write something that could be considered a
    derivative work, and you wish to distribute it, then the GPLv2 obligates
    you to distribute that work under the GPLv2 or a compatible license.
    Most versions of BSD-style licenses, the MIT license, and many others
    are GPLv2 compatible. Many open source licenses are not; the Free
    Software Foundation maintains a page on their website covering this topic.

    * The GPLv2 places no restrictions on how you build your works, where
    you place the source code, or anything of the sort.

    * The module loader in Asterisk, as distributed by Digium under the
    terms of the GPLv2, does make a simple check to ensure that modules that
    are being loaded into a running Asterisk instance claim to be licensed
    under the GPLv2 (or a compatible license) themselves. This is an effort
    to ensure that someone distributing such a module will be aware that
    they need to consider the license under which they distribute it. If you
    want to produce your own modules and distribute them inside your
    organization without putting the ASTERISK_GPL_KEY into them (although
    for distribution inside your organization this won’t really make much
    difference), you can certainly modify the module loader to skip this
    check (you do have the source code, after all).

  • This is strictly true, but of course any decisions to allow or disallow
    distribution of a derived work are made by the party(ies) who
    distributed the original work under the GPLv2; if they choose to allow
    distribution under more permissive licenses, they can certainly do so.

  • This is not true. Distribution in source or binary form makes no
    difference; if you produce an Asterisk module (that falls under the
    ‘derivative work’ classification), whether you distribute it in source
    or binary form you must distribute it under the terms of the GPLv2
    unless you have been granted explicit permission to do otherwise.

    Of course, as I said in my original reply, anyone who has plans to
    distribute Asterisk-derived works and wishes to do us under any license
    other than the GPLv2 would be wise to consult legal counsel in their
    area to learn how the license affects their plans.

  • I shall contact when(and if) decision will be made. But such decision
    cannot be made basing only on this paragraph, because it does not
    describes anything. There are no description of licensing procedure,
    nor pricing, nor liability, rights or freedoms(at least in general
    approximation) of sides. So I’m here asking and asking again.
    In any case, even usage of GPL-ed copy of Asterisk(or any other
    software) is illegal in my country.

  • Why would you expect a single paragraph in the Asterisk source tree to
    have a complete description of Digium’s commercial licensing options? It
    wouldn’t even make sense for that to be in the source tree, disregarding
    that commercial license terms are typically negotiated with each
    customer based on their unique situation.

    Your last question doesn’t make any sense; you are asking us if usage of
    GPLv2-licensed software is illegal in your country? We don’t even know
    what country you live in, and even if we did, the answer to that
    question is something you need to obtain from people who clearly
    understand your country’s laws.