Besides the fact that it has a larger address space, IPv6 also has many other advantages over IPv4: built-in features like support of multicast transmission, increased security with IPSec (providing confidentiality, authentication and data integrity) and the ability to display, in the 4D client connection dialog box, all the 4D Server available even if they are published on a non standard port (different than 19813).
4D introduced IPv6 support with 4D v14, however some dialogs were not perfectly arranged for the IPv6 use cases. 4D v16 R4 provides some UI improvements for a better user experience for people using IPv6 network configurations.
With the new network layer, we can implement new functions that were impossible with the legacy network layer. The first is the application sleep notification.