KPI
Key Performance Indicator: a measurable metric derived from network counters that quantifies network performance in areas like accessibility, retainability, and mobility.
A KPI is the number management actually looks at, and it's almost never a raw measurement — it's derived from counters, usually as a ratio or rate. Accessibility, for instance, is basically "of the attempts to set up a service, how many succeeded?" Retainability is "of the calls/sessions that got up, how many stayed up?" The counters underneath (attempts, successes, abnormal releases) come from the network elements; the KPI is the formula on top.
The split worth internalising early is counters versus KPIs. Counters are the raw events defined in TS 28.552; KPI formulas — how you turn those events into accessibility, retainability, mobility success and so on — are defined in TS 28.554. KPIs are typically grouped by what they tell you: accessibility, retainability, integrity (throughput, latency), availability and mobility. Two cautions from the field: a KPI is only as trustworthy as its formula and the counter definitions feeding it, so an apples-to-apples comparison between vendors needs the formulas to match; and a great network-wide average can hide an ugly worst-cell distribution, which is why you almost always look at per-cell as well as aggregate.
Frequently asked questions
- What is a typical accessibility KPI target?
- Operators usually run accessibility (RRC/service setup success) high — commonly targeted in the upper 90s percent, often 98–99%+ on a healthy network — but the exact threshold is set per operator and per service, and it lives in SLA and internal targets rather than the standard. Treat any single figure as indicative. What matters more day to day is the trend and the worst-performing cells: a 99% network average can still hide cells dropping setups, so always check the distribution, not just the headline number.
Related terms
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