Most of these tests need to bypass the TCP/IP stack in order to directly open the network interface, which generally requires administrative privileges or appropriate access rights. The tests are skipped if the user account running these does not have the required rights. Note that some of these tests require a working network interface with actual traffic on it. For example the loop test waits for 10 packets to be received on the network before exiting. If there is no traffic on the interface, this test will block. The memory leak tests do not complete.