Request for open source code covered under GPL, Lesser GPL, and OSI Licenses

The following licenses allow you to run, copy, distribute, study, change, and improve any code covered by these licenses without any restrictions from Zyxel or the Zyxel End User License Agreement (EULA):
To request open source code covered under these licenses, please fill in the form below.
We strongly advise you to consult with your local ISP (Internet Service Provider) before running any firmware installation on the ISP-provided Zyxel device.

Information here.