metrotek Bercut-MMT, Operation Manual

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36 RFC 2544. Measurements
5.2.3 Latency over Time
Figure 5.7. Latency over Time Test Results
Latency over time distribution is used to determine the ability of a device
under testing (DUT) to effectively buffer the traffic.
In the best case, LoT will have small delay increase over short time period
1
.
Quick LoT increase is a result of DUT buffer overflow, and problems may
arise linked to its modes of operation. Smooth increase of LoT indicates that
DUT is able to support the current frames flow.
The diagram shows delay changing during test execution. Horizontal axis
corresponds to the last 60 seconds of a test.
5.3 Frame Loss
Frame loss measurement allows to calculate percent of frames, that were not
transmitted by object under testing (network or device) at constant load, due
to the lack of hardware resources. This measurement may be useful to get
information about network element behavior in case of anomalous network
loading conditions.
1
Measured LoT values depend on the tested equipment type and capabilities.
Bercut-MMT: Ethernet Networks Analysis