Uptime Also referred to as availability, the proportion of time a service is usable by its users. Latency How responsive a service appears to its users. Scale A service’s volume of users and the mixture of workloads the service can handle before latency suffers or the service falls apart. Velocity How fast a service can innovate to provide users with superior value at reasonable cost. Privacy This concept imposes complex requirements. As a simplification, this chapter limits its scope in discussing privacy to data deletion: data must be destroyed within a reasonable time after users delete it.
