To identify system qualities, specify the minimum requirements that your directory service must provide. The following system qualities typically form a basis for quality of service requirements:
Performance. The measurement of response time and throughput with respect to user load conditions.
Availability. A measure of how often a system's resources and services are accessible to end users, often expressed as the uptime of a system.
Scalability. The ability to add capacity and users to a deployed system over time. Scalability typically involves adding resources to the system without changing the deployment architecture.
Security.A complex combination of factors that describe the integrity of a system and its users. Security includes authentication and authorization of users, security of data, and secure access to a deployed system.
Latent capacity. The ability of a system to handle unusual peak loads without additional resources. Latent capacity is a factor in availability, performance, and scalability.
Serviceability. The ease by which a deployed system can be maintained, including monitoring the system, fixing problems that arise, and upgrading hardware and software components.