WEBVTT

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This lab compares clean and impaired link conditions between two Linux endpoints.

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Check the client address, then ping the server to establish a clean baseline.

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On the server, start an iperf3 listener before measuring throughput.

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Run the same client test to record the baseline modeled throughput.

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Close the client terminal and click the cable to open Link impairment.

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Choose Degraded MPLS and apply the profile to this cable.

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Reopen the cable settings to inspect its current bandwidth, latency, jitter and loss.

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Ping the same server again and compare the round trip times with the baseline.

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Repeat the throughput test with the same endpoints and options.

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These are modeled lab results, not measurements of your own network or hardware.

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The Failed transport profile sets the modeled loss value to one hundred percent.

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Ping still shows reachability here; loss settings do not directly drop ICMP echo replies.

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Reset the cable to perfect and reopen the settings to confirm it is clear.

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Repeat ping and the throughput test to confirm that the clean path has recovered.

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On the server, press Control C to stop the listener.

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A new client test is now refused because the listener is stopped, even though ping still succeeds.

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The link is restored and the test listener is stopped. Compare the same test before and after each change.