ICE
Intrusion Countermeasure Electronics
ICE, short for Intrusion Countermeasure Electronics — but pronounced like the substance, is a catch-all for any advanced system that protects a network or computer. When most people think of ICE, they're thinking of Black ICE — programs designed to detect threats and fight back, often harming intruding netrunners or damaging their equipment. Not all ICE is equally good at detecting intruders or dangerous if they detect someone.
Besides Black ICE, people might have heard netrunners talk about the need to self-ICE. This is because they have their brain connected to a lot of different networks and they might well get an intruder into their own system if they're not careful. Most cyberdecks come with some ICE to protect themselves (and to protect proprietary data by the manufacturer), but it will fold quick enough for a skilled runner.
The most famous piece of ICE is the Blackwall. The intruders it tries to block are both anything from the old NET trying to break in, and anyone risking harm to the new NET by breaching the Blackwall from that direction. It's powerful, clever, and deadly to anyone who tries to tamper with it.
