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TCP segment of a reassembled PDU ?


What does it mean?

TCP segment of a reassembled PDU

asked 17 Dec '16, 07:37

luna's gravatar image

accept rate: 0%

One Answer:


It means that

  • Wireshark/TShark thinks it knows what protocol is running atop TCP in that TCP segment;
  • that TCP segment doesn't contain all of a "protocol data unit" (PDU) for that higher-level protocol, i.e. a packet or protocol message for that higher-level protocol, and doesn't contain the last part of that PDU, so it's trying to reassemble the multiple TCP segments containing that higher-level PDU.

For example, an HTTP response with a lot of data in it won't fit in a single TCP segment on most networks, so it'll be split over multiple TCP segments; all but the last TCP segment will be marked as "TCP segment of a reassembled PDU".

answered 17 Dec '16, 13:53

Guy%20Harris's gravatar image

Guy Harris ♦♦
accept rate: 19%