1. A device comprising: a virtual machine detector configured to determine identity information of a virtual machine; a network detector configured to determine identity information of network devices comprising a network segment and store in memory the identity information of the network devices corresponding to the identity information of the virtual machine, wherein the virtual machine resides on the network segment; a reliability calculator further configured to determine a risk level of the virtual machine based on the identity information of the network devices; and an output device configured to output the risk level of the virtual machine.