In the public network, filters are active that prevent, for example, IP or MAC addresses that do not belong to you from being used. Of course, multicast and ARP will also be filtered. In the public network we support the usual MTU of 1500, in private networks there are no filters (not even on MACs) – here you have your own L2 domains with an MTU of up to 9000.
You can create as many private networks as you like, but there is a limitation to a maximum of 8 connected networks per server (the public network also counts here).
Each network connected to the server is its own virtual network card with its own MAC address.