The Every Xinaran starship has a key. it is what connects the AI, Power, computer, and drive systems, and is what initializes the ship for active duty. On larger ships it's rarely removed, but on small scout craft or personal vessels it makes theft far more difficult.

This is the Key to the Triskelion, Ember's Ship. You'd rarely see it in this configuration as the key portions are open. When removed from the ship the side petals collapse and rotate upward to cover the interface crystals. He's had to remove it a few times, when in hostile space. The key's central crystal is entangled with the main AI's core. The AI would no instantly if the key was genuine or not. As a fallback the smaller crystal is also entangled with the hyperspace and jump systems. It cannot execute a jump or faster than light travel without the computer systems detecting both devices as well as ensuring they are inserted into the ship.