In article , Cen wrote: :Do ethernet interfaces support ip unnumbered?
Not usually, in my experience.
:If not, how do ISPs deliver ethernet termination to customers (e.g. via :Metro LAN) who require only 1 public IP address? If it were to be delivered :via traditional ethernet, the minimal address space of /30 would take up 4 :IP addresses; wasting 3 away.
PPPoE is one way, the way often used for ADSL.
Another method, often used for broadband cable, is to use a switched or shared segment and have filters that cut out everything other than broadcasts and traffic directed to the IPs. This might be accompanied by some sort of encryption to prevent people from tapping in before the filters.