SLI (Service Level Indicator)
A Service Level Indicator is a quantitative measurement used to evaluate whether a service is meeting its Service Level Objectives (SLOs), which in turn underpin contractual SLAs. Common telecom SLIs include availability, packet loss, latency, jitter, and call setup success rate. Modern SRE practice manages reliability through SLO error budgets derived from SLIs.
Categories: Operations and Business
SLI in context
OSS/BSS platforms (provisioning, charging, mediation, order management) hold the highest-value subscriber and revenue data on the operator side. They are heavily targeted for fraud and insider abuse and are increasingly in scope for regulatory obligations like NIS2 and the UK Telecoms Security Act.
To place SLI in the wider telecom-security picture, review SLA, KPI, QoS, TPS, Order Management and Slice Security.
Related terms
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