strongSwan is an open-source project distributed under the GPLv2 license. We think the open source model has several advantages over a proprietary product:
We strongly believe in open source and will always distribute strongSwan under a GPL license.
A commercial, non-GPL license is available from secunet Security Networks AG for most most of the components of the strongSwan project (see our docs for a list of GPL-only components).
Optionally, and only in addition to the license, commercial support is available in two levels of response time / SLA, if you have any problem to solve by strongSwan developers.
Please contact us at email@example.com if you are interested or have any questions.