Comment by lifeisstillgood

Very roughly:

SLI - Service Level Indicators - Metrics ie Latency of each request / response cycle

SLO - Service Level Objective - What threshold we are aiming for - 10 ms from request to response averaged over 1 hour period.

SLA - SL agreement - contract with custom yet what happens if we breach (credits given, put the CTO in stocks and throw eggs at him etc)