- A host can have two (or more) network interfaces, each with its own IP address, each in a different broadcast domain with different IP networks.
- Interface 1 might be on a public network and have an IP address of 192.0.2.2/28, while interface 2 might be on the private network and have an IP of 172.16.99.9/24.
- Such a host is called ==multihomed==.
- A multihomed host automatically connects directly to hosts on subnets it’s attached to, using its IP address on that subnet.
- A host can have multiple IP addresses on one network interface through IP aliasing.
- The interface has a primary IP address, but it also answers ARP requests for the aliased IP addresses.
- Aliases are one way for a single host to communicate with multiple IP subnets on one physical Ethernet.
- The host initiates connections from whichever IP address it has on that subnet.