| Evaluation item | Defense information network(A) >> Traffic(A.3) |
| Metric | <A-3-1> Network availability |
| Explanation | A probability that the defense information network can be serviced without interruption |
| Measurement method | X = MTTF/ ( MTTF+MTTR ) |
| Y = X T arg e t v a l u e × 100 (satisfaction ratio of availability) |
| ※ MTTF (Mean Time To Failure): average time of network service |
| ※ MTTR (Mean Time To Repair): average time to recovery after network service outage |
| Data gathering method (Data sources) | ■ System □ Data |
| □ Questionnaires □ Interview |
| ※ Measure with network management systems (NMS) |