Code Gates control access to a server by requiring an authentic code to pass them, and some even inflict harm to Runners that encounter them without the required code. Runners often describe the process of penetrating a code gate as similar to solving a puzzle or navigating a maze, and use specialized icebreakers known as decoders to deal with them. Known code gates include:
Datapike is described by Ele "Smoke" Scovak as "Cheap off-the-shelf data protection. Cheap for them, that is. Not for us."
As explained by Kate "Mac" McCaffrey, the Jinteki-designed Marker "...doesn't do anything in and of itself. It just marks you as an intruder and makes the next ice do all the work."
The NBN code gate called RSVP disguises itself as a series of electronic transactions, tying up the runner's funds in a thousand or so non-existent purchases and refunds. The banks' system of holds and checks means that while not a single credit ever leaves their servers the runner has no available funds. RSVP also has the unfortunate side effect of being entirely legal...strictly speaking.
NBN's Bandwidth code gate is capable of tracking an intruder making a run. As described by Gabriel Santiago, “It tracks you and logs you. If you get in you can just delete the log. But first you have to get in.”
Several code gates take the form of mazes or fortresses, imprisoning intruders inside. It is said of the Haas-Bioroid Gyri Labyrinth that once inside, the only way out is through your own mind. The Jinteki Shiro ("castle" in Japanese) locks the Runner in a fortress of their own mind, where they should be careful what door they open.
Inazuma is a Jinteki code gate that means "lightning" in Japanese, and it is described as trapping Runners in their own reality, paralyzing them and even preventing them from jacking out.
Yagura acts like a 'watchtower' for Jinteki R&D servers, providing advance warning of cyber-intrusion, allowing sysops to filter R&D data before it is accessed by the intruder. As quoted by Michael Muhama: "The 'cyber-war' is a war of information, and in a war of information, advance warning can be as good as a killing blow. "
IQ is a code gate that was created by merging the brainscans of over a hundred of the most intelligent people in Haas-Bioroid’s cerebral database, its effectiveness is limited either by its lack of imagination or the imagination of the sysops who employ it.
Haas-Bioroid has also designed several bioroid ice that act as code gates. Viktor 1.0 challenges all encountered Runners to a game: "My name is Viktor. Nice to meet you. Would you like to play a game?", while Hudson 1.0 is adamantly against games: "I'm not here to play games. The game is over."
The most recent advance in code gate technology is Lotus Field, a Jinteki code gate based on chi resonance mapping. As quoted by sysop Akitaro Watanabe: "Chi resonance mapping has created a while new field of network security. It is unassailable perfection."