In traditional multihoming, you install a second hardware network adapter on a computer that normally possesses only one. Then, you configure both adapters to utilize the same one local IP address. This setup allows a computer to continue using the network even if one or the other network adapter stops functioning. In some cases, you can also connect these adapters to different Internet/network access points and increase the total bandwidth available to use across multiple applications.
An alternate form of multihoming does not require a second network adapter; instead, you assign multiple IP addresses to the same adapter on one computer. Microsoft Windows XP and other operating systems support this configuration as an advanced IP addressing option. This approach gives you more flexibility to control incoming network connections from other computers.
Combinations of the above - configurations with both multiple network interfaces and multiple IP addresses assigned to some or all of these interfaces - are also possible.
The concept of multihoming is increasing in popularity as new technologies are adding more support for this feature. IPv6, for example, offers more network protocol support for multihoming than traditional IPv4. As it becomes more common to use computer networks in mobile environments, multihoming allows helps solve the problem of migrating between different types of networks while traveling.