To disable IPv6 in OS X Lion, you will need to use the Terminal.
- Applications > Utilities > Terminal
- To determine what are all of your Mac’s network interfaces are, issue the following command: networksetup -listallnetworkservices
- To disable IPv6 for wireless, issue the following command:
- networksetup -setv6off Wi-Fi
- to disable IPv6 for Ethernet, issue the following command:
- networksetup -setv6off Ethernet
- To re-enable IPv6, use -setv6automatic instead
To Disable IPv6 on windows click here Disabling-ipv6-on-Windows