Integrated Overhead SIGINT Architecture, or IOSA, incorrectly reported to be codenamed Intruder, was a spy satellite system to be operated by the United States National Reconnaissance Office, which would have replaced the Mentor and Mercury systems. The satellites were reported to have been under development in 1995. The Intruder system was designed to combine the electronic signals intelligence (ELINT) and communications intelligence (COMINT) roles of signals Intelligence (SIGINT) spacecraft, which had previously been performed by different satellites, the Rhyolite and Vortex series respectively.