Dependability and Security Specification

Dependability and Security Specification

Functional Dependability Requirements

define error checking and recovery facilities and protection against system failures and external attacks

Non-functional Dependability requirements

defining the required reliability and availability of the system

excluding dependability requirements

defining states and conditions that must not arise

preliminary risk analysis

risks from systems environment

life cycle risk analysis

risks that emerge during design and development and are associated with the technologies used for system construction

operational risk analysis

risks associated with the system UI and operator errors

risk identification

identify possible risks that might arise

risk analysis

assess the seriousness of each risk

risk decomposition

decompose risks to discover their potential root causes

risk reduction

define how each risk can be eliminated or reduced in design

intolerable risk

must never arise or result in an accident

as low as reasonably practical (ALARP)

must minimize the possibility of risk given cost and schedule constraints

acceptable

consequences of the risk are acceptable and no extra costs should be incurred to reduce hazard probability