DS-KD8003-IME1 and Hik-Connect

Hi,
I'm looking for a Hikvision video intercom system, which I want to integrate into my current Hikvision camera system. My current system is working with "port-forwarding" and doesn't rely on Hikvision servers.
For the Hikvision Video intercom system (DS-KD8003-IME1)...do I really need to use Hik-Connect?...or does it also work with port forwarding?

Thanks,
Herman