An Iris Deactivation Code (IDC for short) is an authorization code given to Tau'ri personnel and their allies which allows them to recognize inbound Stargate travellers as friendly. Since the Tau'ri use an iris to block all incoming wormholes, an IDC is necessary for a traveller to gain access through the Stargate. They are used by both Stargate Command and the Atlantis expedition.
IDCs are transmitted using Garage Door Openers, a wrist-mounted transmitter with a keypad to enter the relevant code. The signal is received by a computer which identifies its origin, and an "All Clear" signal is transmitted back once the iris is open; otherwise, the GDO returns a "Do Not Proceed" message. Each offworld team and Earth's various allies are assigned a specific code. If a code is potentially compromised, a new code is issued, though the system will still recognize old codes. (SG1: "Foothold", "Gemini")
- Jack's iris deactivation code, prior to the events of "Unnatural Selection", was 903224637.