10-Gigabit Ethernet Switch Performance Testing - Ixia

2. Testing for Latency: RFC 2544 Latency Tests
Objective. To determine the latency of the
DUT, and how much it varies with different
frame sizes.
In this test, frames are transmitted for a
fixed duration. Once per second, the test
tags a frame and transmits it halfway
through the duration time. The test
compares the tagged frame's timestamp
when it was transmitted with the
timestamp when it was received. The
difference between the two timestamps is
the latency.
Setup. A minimum of two 10GE test ports
will be used for this test, in conjunction
with the IxScriptmate RFC2544 test.
Latency will be measured in both
directions.
Parameters. Select the test port pairs,
frame size mode and frame sizes, and
number of iterations.
Figure 6. RFC 2544: Latency Test — results.
Methodology
1. Packets will be sent to the DUT from
each 10GE load module starting with
the selected minimum frame size for
an interval that lasts for selected test
duration.
2. The average latency is then
measured.
3. These two steps will continuously
repeat, using selected frame sizes
every interval until it reaches the
maximum frame size selected.
Results. The results of the test show the
latency in nanoseconds (ns) obtained for
each frame size and test port pair. The
results also show the average latencies
across the pairs.
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