This is our old Q&A Site. Please post any new questions and answers at ask.wireshark.org.

Hey, I wrote a dissector,

Some of my messages are not seen by the wireshark, even though the information is inside the .pcap file, and I can see a specific message that doesn't be dissected as my protocol, as "[TCP segment of a reassembled PDU]".

When I turn on the option in the TCP preferences "Validate the TCP checksum if possible.", I suddenly see the message of my protocol, as my protocol - but with an error of checksum:

Checksum: 0xff30 [incorrect, should be 0x1a23 (maybe caused by "TCP checksum offload"?)]
[Bad Checksum: True]

My question is, Why can't I see messages of my protocol before checking this option, and what is this error about?

Thanks ahead...

asked 26 Feb '13, 23:10

hudac's gravatar image

hudac
61111317
accept rate: 50%

edited 27 Feb '13, 01:14

Be the first one to answer this question!
toggle preview

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here

By RSS:

Answers

Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text](http://url.com/ "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:

×1,620
×637
×193
×36

question asked: 26 Feb '13, 23:10

question was seen: 2,414 times

last updated: 27 Feb '13, 01:14

p​o​w​e​r​e​d by O​S​Q​A