[OR] [P2] [S4] [ST] [C7] Scenario Development Framework

[P2] [S4] Chapter 7

Scenario Development Framework

Introduction

Designing severe but plausible scenarios is only the first step; organisations must also adopt a structured and repeatable framework to develop, document, and execute these scenarios effectively.

Without a consistent approach, scenario testing can become ad hoc, inconsistent, and difficult to evaluate or compare over time.

A well-defined scenario development framework ensures that scenarios are:

• Comprehensive (covering all relevant components)
• Consistent (standardised across the organisation)
• Traceable (linked to Critical Business Services and dependencies)
• Actionable (producing meaningful insights and outcomes)

This chapter introduces a practical framework for building robust scenarios, aligned with operational resilience methodology and supported by structured templates and examples.

Purpose of the Chapter

The purpose of this chapter is to provide a structured approach to developing scenario testing cases, ensuring alignment with Critical Business Services (CBS), dependency mapping outputs, and impact tolerance objectives.

Core Scenario Components

A well-developed scenario must include several key components to ensure clarity, realism, and completeness.

Trigger Event

The trigger event is the starting point of the scenario, defining the initial disruption.

Examples include:

• Cyberattack (e.g., ransomware infection)
• Technology failure (e.g., core banking system outage)
• Third-party failure (e.g., payment processor downtime)
• External event (e.g., natural disaster, geopolitical disruption)

The trigger should be:

• Clearly defined
• Relevant to identified risks
• Capable of initiating a chain of disruptions

Affected Critical Business Services (CBS)

Each scenario must specify the CBS being tested.

This includes:

• Primary CBS was directly impacted
• Secondary CBS is indirectly affected through dependencies

Example:

• CBS-2: Payments & Funds Transfer Services
• CBS-1: Deposit and Account Services (indirect impact through transaction processing delays)

This ensures that the scenario remains service-centric and aligned with operational resilience objectives.

Disruption Timeline

The disruption timeline outlines how the scenario unfolds over time.

Typical elements include:

• T0 (Trigger): Initial disruption event
• T+1: Immediate impact (e.g., system outage begins)
• T+2: Escalation (e.g., backlog of transactions, customer complaints)
• T+3: Secondary impacts (e.g., third-party failures, regulatory notifications)
• T+4: Recovery phase

A well-defined timeline:

• Introduces realism and progression
• Allows for scenario “injects” during testing
• Enables assessment of response and recovery timing

Dependencies Impacted

Scenarios must explicitly identify the dependencies affected by the disruption, based on mapping outputs.

Key dependency categories include:

• People: Key staff unavailability, decision-makers affected
• Processes: Disrupted workflows or manual workarounds
• Technology: System outages, data corruption, infrastructure failure
• Third Parties: Vendor outages, service provider failures

This ensures that the scenario reflects end-to-end interdependencies, rather than isolated failures.

Scenario Documentation Template

To ensure consistency and repeatability, organisations should adopt a standardised scenario documentation template.

Recommended Scenario Template

This template provides a structured and auditable format, supporting governance, regulatory review, and internal consistency.

Alignment with Dependency Mapping Outputs

Scenario development must be tightly aligned with the outputs from dependency mapping (Stage 2).

Key Alignment Areas

• Traceability:
  Each impacted dependency should be traceable to mapping tables (people, process, technology, third parties)
• Critical Path Identification:
  Focus on dependencies that are essential to CBS delivery
• Interdependency Validation:
  Ensure that scenarios reflect how disruptions propagate across interconnected components

Example Alignment

By leveraging mapping outputs, scenarios become:

• Data-driven
• Realistic
• Aligned with actual operational structures

Example Scenario Structures

To illustrate the framework, the following are examples of structured scenarios.

Example 1: Cyberattack on Payment Processing System

Scenario Title: Ransomware Attack on Payments Platform

• CBS Affected:
• CBS-2: Payments & Funds Transfer Services
• Trigger Event:
• Ransomware attack encrypts payment processing servers
• Timeline:
• T0: Malware detected
• T+1: System shutdown initiated
• T+2: Transactions halted
• T+3: Customer complaints escalate
• T+4: Recovery from backup initiated
• Dependencies Impacted:
• Technology: Payment processing system
• People: IT and operations teams
• Third Party: External payment gateway
• Objective:
• Validate the ability to process payments within the impact tolerance

Example 2: Third-Party Service Outage

Scenario Title: Failure of External Clearing Network

• CBS Affected:
• CBS-2: Payments & Funds Transfer Services
• Trigger Event:
• The external clearing network becomes unavailable
• Timeline:
• T0: Network outage detected
• T+1: Transactions queued
• T+2: Backlog increases
• T+3: Regulatory reporting impacted
• Dependencies Impacted:
• Third Party: Clearing network provider
• Process: Transaction settlement
• Technology: Integration interfaces
• Objective:
• Assess the ability to manage backlog and maintain service continuity

Example 3: Combined Scenario (Cascading Effects)

Scenario Title: Cyberattack with Staff Unavailability

• CBS Affected:
• CBS-1: Deposit and Account Services
• CBS-2: Payments & Funds Transfer Services
• Trigger Event:
• Cyberattack coincides with reduced staff availability
• Timeline:
• T0: Attack detected
• T+1: System degraded
• T+2: Limited staff availability slows response
• T+3: Multiple CBS impacted
• Dependencies Impacted:
• Technology: Core banking system
• People: Operations and IT teams
• Process: Transaction processing
• Objective:
• Test resilience under compounded stress conditions

A structured scenario development framework is essential for ensuring that scenario testing is consistent, comprehensive, and aligned with operational resilience objectives.

By clearly defining scenario components, adopting standardised documentation templates, and aligning with dependency mapping outputs, organisations can develop scenarios that are both realistic and impactful.

Well-constructed scenarios enable organisations to test not only individual components but also the complex interdependencies that underpin Critical Business Services.

They provide the foundation for meaningful testing, robust evaluation, and continuous improvement.

Ultimately, a disciplined approach to scenario development transforms testing from a theoretical exercise into a powerful tool for resilience validation and organisational learning, ensuring that organisations are prepared for real-world disruptions.