The Cisco IP SLA Layer
Cisco IP SLA is a part of Cisco IOS software that allows administrators to analyze IP service levels for IP applications and services by using active traffic monitoring—the generation of traffic in a continuous, reliable, and predictable manner—for measuring network performance. Cisco IOS IP SLAs can perform network assessments, verify quality of service (QoS), ease the deployment of new services, and assist with network troubleshooting. Using this layer, administrators can determine the status of the monitoring operations performed by an IP SLA, and see detailed metrics reported by the IP SLA for each operation and operation type. This includes metrics such as the round trip time of each operation, packet loss, average latency, count of delayed packets, and packets out of sequence.
Figure 1 : List of tests associated with the Cisco IP Sla layer