Licensing

To that end, the Semantix ASN.1 Compiler is offered under a dual licensing mode:

• Commercial Developer License: The DMT Commercial Developer License is the suggested version to use for the development of proprietary and/or commercial software. This version is for developers/companies who do not want to comply with the terms of the GNU Lesser General Public License version 2.1.
• GNU LGPL v. 2.1: This version of DMT is the one to use for the development of applications, when you are willing to comply with the terms of the GNU Lesser General Public License version 2.1.

By purchasing a Commercial Developer License, you are entitled to one year's worth of premium technical support (via e-mail and phone).

The advantages of getting a commercial license are summarized in the table below:

License type:	Commercial	LGPL
License cost	License fee charged	No license fee
Must provide access to all source code changes back to Semantix	No, modifications can be "closed" to your own system	Yes, all source code of your system must be accessible to everyone
Can create proprietary applications	Yes, no source code needs to be disclosed	Yes, no source code needs to be disclosed
Support	Yes, 12 months of premium technical support (same-workday access via e-mail and instant messaging)	None, but can be purchased separately
Charge for runtimes	None	None, but all your systems's source code must be available
Custom, mission-specific additions to the tools	Yes*	None

This dual licensing scheme is followed by many other businesses (see licenses of Nokia's QT, Oracle/SUN's MySQL, etc). It guarantees the perennity (longevity) of the code, since all the source code of the tools is visible to everyone, while retaining the business case for the efforts behind supporting them - since clients can purchase premium support.