A method and apparatus is disclosed herein for using a virtual security boundary. In one embodiment, the method comprises receiving information from a virtual machine after the virtual machine has been moved from a first physical location in a network to a second physical location in the network, where the information identifies the virtual machine as one previously assigned to a security boundary; determining that access to the virtual machine at the first physical location was permitted by the security gateway; assigning the virtual machine at the second physical location to the security boundary, and applying a security policy associated with the security boundary to communications between the network and the virtual machine at the second physical location.