After some research I saw that IPSec is built-in in iOS Network Extension. Unfortunately, IPSec does not fit our needs.
OpenVPN would be great for our needs but it needs custom implementation of the OpenVPN source code - which is something we would like to avoid because of the difficulty of estimate the amount of work and license issues.
That's why I would like to know if there are other built-in VPN protocols than IPSec in iOS Network Extension so that I can check if it could meet our needs.
In Network extension, there is the class NEVPNProtocol. In the description of this class, we can see that the class NEVPNProtocolIPSec implements IPSec VPN. But I can't see any other VPN built-in protocol.
Could anyone tel me if he knows of other VPN built-in implementation than IPSec ?
Thanks in advance,