Sunrise telecom XTT 5000, User Manual

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XTT 5000 User's Manual
Technology: Frame Interval Home
Frame Interval : The time between the start of one frame and the start of the next
frame. The frame interval increases as the frame size increases. However, as the
effect of frame size is usually very small compared to the duration of traffic
problems, the frame interval is useful for measuring service disruptions.
Minimum Frame Interval Note
Under normal network conditions, the smallest possible frame interval is for two 64-
byte frames with a minimum frame gap. This is:
(64 + 20 bytes) x 8 bits / byte or 672 bit times.
For Gigabit Ethernet, the bit time is 1.0 ns, making the minimum frame interval 672
ns over Gigabit Ethernet.
Undersized frames or abnormally small frame gaps will reduce the frame interval
further.
Maximum Frame Interval Note
This value is also used as the basis for the Service Disruption measurement.
If there is a network disruption on the far side of a switch from the test set, the only
indication of a problem will be an increase in the frame interval.
Because these disruptions are on the order of tens of milliseconds, the minor
variances in frame interval caused by shorter or longer frames is negligible.
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Tech: Ethernet Frames
Summary Results
Aggregate Results
Throughput Stream Results
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