Each system is separated into several nodes forming the network. Nodes are interconnected by links and users can only move from node to node using these links.
This node is the first node you will connect to in the network. Functions as a gateway to the whole network and from the network to outside global net. Access nodes can be also encountered inside the system and provide a portal to other access node deeper in the system, effectively making a shortcut.
These nodes have no specific function, they are empty space on crossings of links between other nodes.
IO Nodes are controllers of external systems. They can control anything from cameras and doors to security systems and power generators for whole factories. They can be enabled or disabled by deckers, which will affect the external system. Contracts often require decker to disable a specific IO node to complete the mission.
Data nodes contain database files and are the most common targets for contract missions. Files have different types and can be valuable, contain source of a program, passcode or a clue to finishing mission. Each file must be analyzed before the type is determined and scanning takes time during which the decker must remain in the node. Moving from the node during the scan will abort the process. Valuable files then can be further evaluated by a software to determine market price, this allows decker to focus on files they can sell for highest price on the market.
Files can be downloaded, edited or deleted, specified by mission contract. Deleting a file that is required to be downloaded as a mission goal will fail the mission. Some files can be secured by worm ICE, this ICE will delete the file if it detects unauthorized access to the file.
These nodes act as a house for ICE guarding the system. Often there is reaction group of ICE waiting in the security node. When alert is raised somewhere in the system, this reaction force is sent to investigate and control the intruders. Security node also controls any trace that is running – attempt to find the intruder’s location. Trace can be cancelled only from this node.
Security node also allows to lower system alert level after alert was raised somewhere in the system. When yellow or red alert is raised, all ICE in system are more effective as more system resources are released for ICE and security usage. Lowering the alert level will reduce the effectiveness of ICE systems back to normal state. Security node usually has higher rating than other nodes to make it more secure against decker actions.
CPU node is the heart of the system. There is only one CPU node per system and acts as control center for all other nodes and has the best protection. Rating of other nodes cannot be higher than that of CPU node, meaning rating of CPU node decides the maximum rating for whole network. Deckers can get a map of whole system from this node which allows them to effectively plan route to parts of the system they need to access.
Decker can also use CPU node to install a backdoor malware. This allows anyone with access code for the backdoor to connect directly to the CPU node, avoiding all of the security and ICE constructs of other nodes. Because of this high risk, CPU nodes are heavily guarded and put in the most secure parts of system network.
Because CPU node controls all other nodes, it can be used to start a system shutdown. This can be initiated by decker to perform a sabotage, or it can be initiated by ICE to protect the system from intrusion. Once the shutdown is initiated, there is a short window during which it can still be aborted. Again it can be aborted by decker or ICE. If shutdown is not aborted, whole system is powered off and all users are immediately disconnected.
This node is a specialized type of IO node. It serves to alert operators of the system that intrusion is detected. When red alert is raised in system, this node will send message to system operators that can then act to protect system. They can initiate shutdown, activate more ICE or send a human operator inside the system to counter the intrusion. This node can be disabled the same way an IO node is disabled, which will prevent alerting the operators.
This is a special access node type that allows alternate access to system for human operators and additional ICE constructs. If alert is raised in the system, operators or ICE can be sent to this node to gain quicker access to inner parts of the system and allow them faster response. This node can be also disabled to prevent access and forces the reinforcements to enter system through normal access node.