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Subject: System Resilience

System Resilience Part 7: 16 Guiding Principles for System Resilience

System Resilience Part 7: 16 Guiding Principles for System Resilience

• SEI Blog
Donald Firesmith

Adverse events and conditions can disrupt a system, causing it to fail to provide essential capabilities and services. As I outlined in previous posts in this series, resilience is an essential quality attribute of most systems because they provide critical capabilities and services that must continue despite the inevitable adversities. These adversities are often unavoidable and come in many forms. Typical examples include coding defects (robustness), hazards and accidents (safety), vulnerabilities and attacks (cybersecurity and...

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System Resilience Part 6: Verification and Validation

System Resilience Part 6: Verification and Validation

• SEI Blog
Donald Firesmith

Adverse events and conditions can disrupt a system, causing it to fail to provide essential capabilities and services. As I outlined in previous posts in this series, resilience is an essential quality attribute of most systems because they provide critical capabilities and services that must continue despite the inevitable adversities. In the first post in this series, I defined system resilience as the degree to which a system rapidly and effectively protects its critical capabilities...

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System Resilience Part 5: Commonly-Used System Resilience Techniques

System Resilience Part 5: Commonly-Used System Resilience Techniques

• SEI Blog
Donald Firesmith

If adverse events or conditions cause a system to fail to operate appropriately, they can cause all manner of harm to valuable assets. As I outlined in previous posts in this series, system resilience is important because no one wants a brittle system that cannot overcome the inevitable adversities. In the first post in this series, I addressed these questions by providing the following, more detailed, and nuanced definition of system resilience: A system is...

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System Resilience Part 4: Classifying System Resilience Techniques

System Resilience Part 4: Classifying System Resilience Techniques

• SEI Blog
Donald Firesmith

A system resilience technique is any architectural, design, or implementation technique that increases a system's resilience. These techniques (e.g., mitigations, such as redundancy, safeguards, and cybersecurity countermeasures) either passively resist adversities, actively detect adversities, react to them, or recover from the harm they cause. System resilience techniques are the means by which a system implements its resilience requirements. Resilience techniques can also be viewed as architecture, design, or implementation patterns or idioms. This post begins...

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System Resilience Part 3: Engineering System Resilience Requirements

System Resilience Part 3: Engineering System Resilience Requirements

• SEI Blog
Donald Firesmith

At its most basic level, system resilience is the degree to which a system continues to perform its mission in the face of adversity. While critical to operational continuity, the system's services (capabilities) are only some of the assets the system must protect to continue to perform its mission. The system must detect adversities, react to them, and recover from the harm to critical assets that they cause. System resilience at a deeper level is...

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System Resilience Part 2: How System Resilience Relates to Other Quality Attributes

System Resilience Part 2: How System Resilience Relates to Other Quality Attributes

• SEI Blog
Donald Firesmith

To most people, a system is resilient if it continues to perform its mission in the face of adversity. In other words, a system is resilient if it continues to operate appropriately and provide required capabilities despite excessive stresses that can or do cause disruptions. System resilience is not an isolated quality attribute. As this post, the second in a series on system resilience, details, it is directly related to robustness, safety, cybersecurity, anti-tamper, survivability,...

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System Resilience: What Exactly is it?

System Resilience: What Exactly is it?

• SEI Blog
Donald Firesmith

Over the past decade, system resilience (a.k.a., system resiliency) has been widely discussed as a critical concern, especially in terms of data centers and cloud computing. It is also vitally important to cyber-physical systems, although the term is less commonly used in that domain. Everyone wants their systems to be resilient, but what does that actually mean? And how does resilience relate to other quality attributes, such as availability, reliability, robustness, safety, security, and survivability?...

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