Embodiments for securely determining a separation distance between wireless communication devices is provided. These embodiments include receiving a measurement request and a first random identifier from a first wireless communication device at a second wireless communication device. The embodiments also includes deriving a transient key using the first random identifier, a second random identifier (generated by the second device), and a pre-shared key. The first and second random identifiers, the pre-shared key, and the transient key derived therefrom are shared between the first and second devices, but are not known to any other devices. The embodiments further include encrypting measurement data exchanged between the two devices using the transient key, and using the encrypted measurement data to calculate and verify a separation distance between the devices. The embodiments thus prevent dishonest wireless communication devices from intercepting communications and spoofing a location of one of the two honest devices.