Overview
ISO/IEC TR 23951:2025 - "Information technology - Cloud computing - Best practices for using the cloud service level agreement (SLA) metric model" - provides practical guidance on applying the metric model defined in ISO/IEC 19086-2. The technical report explains how to compose, clarify and share measurable cloud SLA metrics (SLOs and SQOs) and uses worked examples (notably Cloud Service Mean Response Time and Simple Cloud Service Availability) to illustrate best practices. It refines the metric-model tables from ISO/IEC 19086-2 into a tabular representation that serves as reusable templates for metric design.
Key topics and requirements
- Metric model usage: Guidance on how to apply the ISO/IEC 19086-2 metric model to create consistent, unambiguous SLA metrics.
- Tabular templates: A structured tabular format (refinement of Annex B in ISO/IEC 19086-2) for defining Metric, Expression, Rule and Parameter elements.
- Examples and variants: Worked examples including informal and more formal metric variants (mean response time) and alternative availability metric designs.
- Guidelines and patterns: Practical guidelines covering expression and rule languages, linking rules to expressions, identifier conventions, parameters, and constants.
- Audience and use cases: Describes roles (Cloud Service Customer - CSC, Cloud Service Provider - CSP, Cloud Service Partner - CSN, regulators, policy makers) and common usage patterns such as extracting metric definitions from SLAs, creating/sharing metrics, comparing metrics, and building metric catalogues.
- Alignment and references: Technical revision aligned with ISO/IEC 22123 and referencing related cloud standards (e.g., ISO/IEC 19086 series).
Practical applications and who would use this standard
- Cloud service providers (CSPs): To define measurable SLOs/SQOs in SLAs, ensure consistency across offerings and enable automatable measurement.
- Cloud service customers (CSCs): To verify SLA commitments, compare provider metrics and interpret metric definitions clearly.
- Service integrators/partners (CSN): To translate SLA metrics across combined services and contract boundaries.
- Regulators and procurement teams: To standardize requirements and assess compliance against well-defined metrics.
- Tool and platform developers: To implement monitoring, alerting and reporting systems that compute metrics consistent with ISO models.
Related standards
Keywords: ISO/IEC TR 23951:2025, cloud SLA, SLA metric model, ISO/IEC 19086-2, cloud metrics, SLO, cloud service availability, mean response time, cloud service level agreement, metric templates.