The default location UUID can be obtained in the root of the PropertyList as the key 'CurrentSet'. Then you would also manipulate the particular Location you want this NetworkService for (remember Mac OS X can configure all network interfaces dependent on your 'Location'). IPv4 configuration and set the interface to your tun or tap device (i.e.The Ethernet entry can be copied pretty much verbatim, the only fields you would actually be changing are: The place to create the new NetworkService is under 'NetworkServices', and if your Mac has an Ethernet device the NetworkService profile will also be under this property entry. Basically you would open the ist file in Xcode (or edit the XML directly, but Xcode is likely to be more fool-proof), and copy the configuration from an existing Ethernet interface. Mac OS X will not allow the creation of a NetworkService based on a virtual network interface, but one can directly manipulate the ist file to add the NetworkService by hand. This can be achieved using a Tun/Tap device as suggested by psv141, and manipulating the /Library/Preferences/SystemConfiguration/ist file to add a NetworkService based on either a tun or tap interface. Unfortunately, no interface is resolving DNS names if none of them are inactive. By configuring an interface to use the virtual DNS server, I thought I could test some DNS scenario's. Those virtual machines can be reached by their IP address, but not by their DNS name, even if I run a DNS server in one of those virtual machines. Even then, it makes sense to have networking capabilities when running servers in a VMWare installation. This scenario is needed when working in a completely disconnected situation. You can create a new interface in the networking panel, based on an existing interface, but it will not act as a real fully functional interface (if the original interface is inactive, then the derived one is also inactive). I know that you can make a virtual network interface in Windows (see here), and in Linux it is also pretty easy with ip-aliases, but does something similar exist for Mac OS X? I've been looking for loopback adapters, virtual interfaces and couldn't find a good solution.

Virtual cable for mac