Failure Classification

A failure always depends on the expected system function.

Physical Link Failures

• Link break: Loss of physical connection due to cable cut (wired net) or movement out of range (wireless net)
• Noisy Channel: Destruction of signal due to external events: electro-magnetic interference
• Episodic Connectivity

Node Hardware Failures

• Node destruction: node is permanently down
• Interface failure: defective hardware (sender/receiver)
• Hardware implementation mistake: Error in packet processing, i.e. unable to process maleformated packets blocks interface
• Hardware defect due to aging