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Update to Noteworthy Reports to update unidirectional reports authored by Max Holicki's avatar Max Holicki
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Noteworthy-Reports.md
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...@@ -59,9 +59,9 @@ Bidirectional testing is a different type of test entirely. Uni- and semi-direct ...@@ -59,9 +59,9 @@ Bidirectional testing is a different type of test entirely. Uni- and semi-direct
What this means for bidirectional testing is that it should be used only when bidirectional communication is expected to cause communication congestion that will cause both messages to be transferred slower, or to test if this is the case. Bidirectional testing cannot pick up on network-topology anisotropy between nodes, it can, however, measure congestion effects when trying to communicate in both directions at the same time. What this means for bidirectional testing is that it should be used only when bidirectional communication is expected to cause communication congestion that will cause both messages to be transferred slower, or to test if this is the case. Bidirectional testing cannot pick up on network-topology anisotropy between nodes, it can, however, measure congestion effects when trying to communicate in both directions at the same time.
Let us now illustrate this with an example. We have a network with two nodes `Mew` and `Mewtwo` and an auxiliary node, the `Pokémon Center`. We now conduct uni-, semi- and bi-directional tests between the nodes and find that the results between the nodes for all three tests are very similar. Here are the [reports](uploads/7014b87de21ff7e8dc6bd09646180e69/Pokemon.pdf). Let us now illustrate this with an example. We have a network with two nodes `Mew` and `Mewtwo` and an auxiliary node, the `Pokémon Center`. We now conduct uni-, semi- and bi-directional tests between the nodes and find that the results between the nodes for all three tests are very similar. Here are the [reports](uploads/fbc5f106e7eb4795494d0625a26fae5b/Pokemon.pdf).
Now `Mewtwo` catches `Pokérus`, which causes it to have to send messages with a size greater than 1 kiB via `Bill's PC`, which is only reachable via the `Pokémon Center`. All of a sudden messages from `Mewtwo` to `Mew` take twice as long to arrive. This effect can be measured. Redoing the three tests we find very different results. Here are the [reports](uploads/bb76e7dd1097b9c49f0fd788d17fe705/Pokemon_Pokerus.pdf). Now `Mewtwo` catches `Pokérus`, which causes it to have to send messages with a size greater than 1 kiB via `Bill's PC`, which is only reachable via the `Pokémon Center`. All of a sudden messages from `Mewtwo` to `Mew` take twice as long to arrive. This effect can be measured. Redoing the three tests we find very different results. Here are the [reports](uploads/cd3978040b6e87e9d7b4370a65e5c2de/Pokemon_Pokerus.pdf).
The changes make sense when we think of the discussion above. The network topology is now anisotropic between `Mew` and `Mewtwo`, which causes the unidirectional connection between `Mewtwo` and `Mew` to be slower. This has knock-on effects to the semi- and bi-directional tests causing the measured times to be larger. The changes make sense when we think of the discussion above. The network topology is now anisotropic between `Mew` and `Mewtwo`, which causes the unidirectional connection between `Mewtwo` and `Mew` to be slower. This has knock-on effects to the semi- and bi-directional tests causing the measured times to be larger.
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