| 1. The property of being accessible and usable upon demand by an authorized entity
(Source: ISO/IEC 13335-1:2004)
2. The property of a system or a system resource being accessible and usable upon demand by an authorized system entity, according to performance specifications for the system; i.e., a system is available if it provides services according to the system design whenever users request them.
(Source: RFC 2828) |