"IC" ICE INTRUSION COUNTERMEASURES Interference Countermeasures, or IC, are computer programs designed to protect a system from hackers. IC may be installed in any system with a node rating of green or higher. Every IC has a rating, which is it's skill and target number for any tests made against it. There are three classes of IC: White, Gray, and Black. White IC are passive and only act as doorway guards. Gray IC actively attacks intruders or traces their entry point into the Matrix. Black IC will try and actually kill deckers. See Also: CYBERCOMBAT, MATRIX, DUMPSHOCK