Licensing
AGPL-3.0, or a commercial licence. Pick the arm that fits what you ship.
The two arms
AGPL-3.0-only
The free arm
Use Sipral at no cost. If you give your application to anyone else, the whole application, Sipral included, has to reach them under the AGPL-3.0 with its source; section 13 also lets you combine it with code under the GPL-3.0.
The AGPL adds one obligation over the plain GPL: if you run a modified Sipral as a network service, the people using that service must be able to get your source. Running a SIP endpoint on your server for someone else to call counts.
LicenseRef-Sipral-Commercial
The commercial licence
- One price per company
- Perpetual for the versions delivered during the maintenance term
- No royalties, no per-seat and no per-channel counting
- No NDA required, no obligation to disclose your source
- An explicit right to distribute through app stores
Prices are quoted privately. Asking does not announce anything about your product.
Which one you need
Charging for a copy is not the trigger; the AGPL allows that. Withholding the source is.
| What you are building | Arm |
|---|---|
| Open source app under AGPL-3.0 | Free |
| Research, teaching, evaluation, a prototype you do not ship | Free |
| Closed-source desktop, mobile or on-premises server product that you distribute | Commercial |
| App Store or Google Play distribution | Commercial |
| Hosted service using a modified Sipral, source not published | Commercial |
| SDK or library you resell with Sipral inside, its own source not under AGPL-3.0 | Commercial, under an OEM agreement |
The fine print, in plain words
Third-party code
Sipral links only permissively licensed dependencies: MIT, BSD, Apache-2.0, ISC, Zlib and a few equivalents. None of them restricts either arm. The dependency allow-list is enforced by the build, and their licence texts are generated into one file that ships with your binaries.
Patents, and one codec in particular
A licence on source and a patent reading on what that source does are different things. Opus is the subject of a patent pool that names IP phones among the product categories it pursues. Sipral shipped as software on its own is outside what that programme says it currently pursues; a handset with Sipral inside is in a category it names. If your product cannot carry that exposure, a build without Opus links no libopus at all and leaves G.711, G.722 and G.729.
The name
The licences cover the code, not the name. You may say your product uses or is built with Sipral, and write about it. Naming your own product, company or package Sipral, publishing a modified build under the name, or suggesting endorsement needs written permission. A fork is a right the AGPL gives you: ship it under a different name.
Questions answered
Is Sipral free to use?
Yes, under the AGPL-3.0-only licence. If you give your application to anyone else, the whole application, Sipral included, has to reach them under the AGPL-3.0 with its source. Research, teaching, evaluation and copyleft open source products fit this arm.
When do I need the commercial licence?
When your application is closed source and you distribute it, when you ship it through the App Store, Google Play or any store whose terms conflict with the AGPL, when you run a modified Sipral as a service without publishing your source, or when you embed it in a product you resell without releasing that product's source.
What does the commercial licence cost?
One price per company, quoted on request through the contact form. It is perpetual for the versions delivered during the maintenance term, with no royalties and no per-seat or per-channel counting.
Is there a licence check inside the library?
No. The commercial arm is a contract, not a runtime lock.
Anything else about licensing goes through the contact form. It is private, and it is the preferred route: you should not have to announce in public that your product is closed source in order to ask a question about licensing it.
Ship SIP in a closed app, without the GPL.
One price per company, perpetual for the versions delivered during maintenance, app stores allowed. Ask privately.
Request a quote