Service level management fundamentals and concepts
Domain 1 tests the vocabulary and mental model that every later domain assumes. Expect questions that ask you to separate an SLA from an OLA and an underpinning contract, to spot a target that is technical rather than business-based, and to place a scenario in the right step of the SLM cycle.
Purpose in one line
ITIL 4 defines service level management (SLM) as the practice that sets clear, business-based targets for service levels and ensures delivery is properly assessed, monitored and managed against them. Unpack it: business-based (traced to customer outcomes, not server statistics), assessed (measurable from a named source), managed (a repeating cycle, not a signed document in a drawer).
Terms you must not blur
- Service level requirement (SLR): what the customer needs, captured before negotiation.
- Service level agreement (SLA): documented agreement between provider and customer naming the services and expected levels.
- Service level objective (SLO): a measurable target inside or beneath an SLA.
- Operational level agreement (OLA): internal agreement between teams in the same organization.
- Underpinning contract (UC): agreement with an external supplier. Hierarchy rule: OLAs and UCs must be at least as demanding as the SLA they underpin, or the provider has promised what it cannot deliver.
The cycle
Engage, capture SLRs, negotiate, agree SLA and SLOs, monitor, report, review, improve. Every scenario question maps to one of these steps.
Worked example
A retailer’s checkout is losing sales. IT proposes “CPU below 70%” - a proxy nobody buys. Rewrite: “95% of checkout transactions complete in under 2 seconds between 08:00 and 22:00, measured at the load balancer by synthetic transactions every minute, reported monthly, reviewed quarterly.” Then confirm the platform team’s OLA and the payment provider’s UC support that figure.
Traps
Swapping OLA and UC; writing an SLA as a technical specification; measuring uptime only while customers complain about slowness; skipping the review so the SLA ages out of relevance.