In some versions of Windows, this will turn off the ability to route "source routed" packets. However, there is a bug in some older versions of Windows that would allow source routed information to pass through the system despite this flag being turned off.
Value Name: DisableIPSourceRouting
Data Type: REG_DWORD
Value: 0 , 1 or 2
Note: 0 - enables source routing
1 - disables source routing when IP forwarding is also enabled
2 - disables source routing completely (recommended for best security)