Service Level Agreements (SLAs) typically require that performance data is collected over five-minute (or longer) measurement intervals. Network optimization tools require average performance values to be computed over shorter periods of time. The OAM-PM streaming function takes advantage of the OAM-PM architecture and test definitions to provide the basis for short window average results streaming.
The delay-template configuration allows users to define the common parameters: metric type, direction, length of the sample window, and integrity value. After the template is defined, it can be assigned to the appropriate technology to support tests for collection, calculation, and reporting. The results of the process are sent using on-change update notifications to subscribers.
The streaming function is supported for Ethernet DMM tests and IP TWAMP-light (delay) tests.
The updates are sent only if a subscription is registered for the on-change values. The keys are common for each individual test: session session-name, metric metric-id, and newest-closed direction. The following values are sent for each completed sample window:
close-time (UTC)
sample-count (number of samples used to compute delay)
suspect (equal to or greater than the window-integrity percentage = no | lower = yes)
delay (compute value over the window in micro-seconds)
No history is maintained on the node for this information. The single statistic is overwritten every time a sample window closes for a test configured to use a delay template. The higher-level systems are responsible for storing and using this data.