|Usage and history|
A code cylinder was a common security device used by military officers, corporate executives, and politicians. It acted as a sophisticated keycard for secure areas. Each cylinder contained its user's personal security clearance codes and data. It was not uncommon for high-ranking personnel to own multiple code cylinders, each with their own encrypted access codes. They were used extensively in the Galactic Republic, Galactic Empire, and New Republic, particularly to facilitate security measures. The devices, usually carried within a pocket or on one's belt, used the same interface as a droid's scomp link.
Code cylinders could be reprogrammed. In situations where it was impossible for a slicer to be physically present and hack a security door, they sometimes elected to reprogram the cylinder instead. Cylinders were programmed with countermeasures such that a failed reprogramming caused the data to become irretrievably corrupted.
During the Jedi Civil War, the Sith officer Commander Doel Scherp was entrusted with a code cylinder that contained the command codes for the sensor systems of Darth Revan's flagship. In approximately 3,957 BBY, a team of Republic agents stole the code cylinder from Scherp's Estate on the planet Sernpidal, and took the device to a rendezvous point with the Republic fleet, on the Republic's border with the Sith Empire. The Republic subsequently used the information contained within the cylinder to attack the flagship, and capture Darth Revan.