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Out of order on point-to-point connection

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Is it possible to have out of order packets in wireshark ok point to point connection? I mean, no switch, no router between hosts. Simply two server connected each other by 10Gb ethernet cable.

Thank you.

asked 08 Jul '14, 22:13

becco981's gravatar image

becco981
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edited 29 Mar '15, 19:04

Guy%20Harris's gravatar image

Guy Harris ♦♦
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One Answer:

1

I guess that's being caused by the NIC driver. As you mentioned 10Gb, chances are good that there is at lease some 'intelligence' in the NIC and who knows how the driver decides in which order to deliver the received frames to the OS, especially on a multi CPU system and also considering checksum offloading and TCP segment offloading.

So, yes packet reordering (as shown by Wireshark) can happen on a direct link. My bet for the most likely reason: the NIC driver

Regards
Kurt

answered 09 Jul '14, 01:31

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
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edited 09 Jul '14, 01:32

Thank you. Just one more clarification: in wireshark I can see out of order packets only after "Previous segment not captured". Are they really out of order or they're just a consequence of not captured packets?

(09 Jul '14, 21:47) becco981

More likely the later one.

(10 Jul '14, 01:05) Kurt Knochner ♦