Asterisk is distributed under the GNU General Public License version 2

and is also available under alternative licenses negotiated directly

with Digium, Inc. If you obtained Asterisk under the GPL, then the GPL

applies to all loadable Asterisk modules used on your system as well,

except as defined below. The GPL (version 2) is included in this

source tree in the file COPYING.

This package also includes various components that are not part of

Asterisk itself; these components are in the 'contrib' directory

and its subdirectories. These components are also distributed under the

GPL version 2 as well.

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.

If you wish to use our code in other GPL programs, don't worry --

there is no requirement that you provide the same exception in your

GPL'd products (although if you've written a module for Asterisk we

would strongly encourage you to make the same exception that we do).

Specific permission is also granted to link Asterisk with OpenSSL, OpenH323

UniMRCP, and/or the UW IMAP Toolkit and distribute the resulting binary files.

In addition, Asterisk implements several management/control protocols.

This includes the Asterisk Manager Interface (AMI), the Asterisk Gateway

Interface (AGI), and the Asterisk REST Interface (ARI). It is our belief

that applications using these protocols to manage or control an Asterisk

instance do not have to be licensed under the GPL or a compatible license,

as we believe these protocols do not create a 'derivative work' as referred

to in the GPL. However, should any court or other judiciary body find that

these protocols do fall under the terms of the GPL, then we hereby grant you a

license to use these protocols in combination with Asterisk in external

applications licensed under any license you wish.

The 'Asterisk' name and logos are trademarks owned by Digium, Inc.,

and use of them is subject to our trademark licensing policies. If you

wish to use these trademarks for purposes other than simple

redistribution of Asterisk source code obtained from Digium, you

should contact our licensing department to determine the necessary

steps you must take. For more information on this policy, please read:

https://www.sangoma.com/wp-content/uploads/Sangoma-Trademark-Policy-1.pdf

If you have any questions regarding our licensing policy, please

contact us:

+1.877.344.4861 (via telephone in the USA)

+1.256.428.6000 (via telephone outside the USA)

+1.256.864.0464 (via FAX inside or outside the USA)

licensing@digium.com (via email)

Digium, Inc.

445 Jan Davis Drive

Huntsville, AL 35806

USA