IPv4 and IPv6 traffic routing on multihomed systems
If you’ve ever used a computer with both a wireless and a wired connection, you’ve used a “multi-homed” computer. With Server 2003 and Windows XP, you may be familiar with the scenario where you’re using a multihomed computer to perform a file download, and you realize that you’ve forgotten to plug in your LAN cable. Realizing that the download would be faster over the wired network, you plug in, and once your wired connection initializes, the download speeds up.
Interestingly, this little trick no longer works in Server 2008 and Windows Vista. Longhorn operating systems use something called the “strong host model,” which basically says that receive packets will only be accepted on the IP address to which they are addressed. (The same rule applies for outgoing packets, too.) So with these operating systems, you’ll need to restart that file download after plugging in your LAN cable.
The strong host model provides better security on multihomed systems that are exposed both to internal and external networks. However, if you want to disable it, you can, using the command-line tool netsh with a parameter such as weakhostreceive=enabled.
Recent posts:
