Imperial Security Operations (ISO) was an organization within the Galactic Empire's Imperial Security Bureau. It was the center of covert operations and intelligence for the Empire and was based in Imperial City on Coruscant.
The main building was a maximum security area with all posts alert at all times. From the roof, an elevator led to a security vault deep below the building. It hosted a reader that could interpret Imperial secret codes that had been written to nava cards, among other types of memory circuits. The machine was fairly inaccessible; anyone wanting to access the terminal without authorization had to pass through a complex system of concentric circles, separated by gates that were controlled by switches on the outermost concentric corridor. Normally, Imperial Officers stationed around the perimeter would activate them remotely, providing fairly comprehensive security; one could not access the central core without first getting permission from the six security officers.
Kyle Katarn managed to break into the building in order to decode a nava card that he had obtained earlier from Nar Shaddaa and write the Executor's current star-route on to a set of data disks, in order to find the secret location of the Arc Hammer.