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networking - Wireshark - how can I observe little endian big endian difference in byte order using Wireshark?


I wrote a simple application which communicates using UDP sockets (in C). Application is simple: clients sends numbers to server, and server computes the sum of them.


Now, I know how can I capture the packets exchanged by client and server, but I wonder how can I, using Wireshark, observe the difference between little endian and big endian byte order for my packets?



Answer



On Wireshark not recognized protocols you will only see TCP or UDP packets with a "non-parsed" payload field. if the protocol "is" recognized by Wireshark (BOOTP, DHCP, DNS, SMB, HTML, etc etc) you will see that Wireshark "shapes" the TCP/UDP payload area displaying the corresponding recognized higher level protocol fields.


Wireshark has included many dissectors for well known protocols and you can create your own if you want to display your particular protocol payload in a formatted way; see here. https://www.wireshark.org/docs/wsdg_html_chunked/ChDissectAdd.html


in your case your dissector can deal with the "endianness" of a particular field handling permitted values.


Please consider a byte sequence is just that, "endianness" on the other hand is the first of several nested layers of numeric information representation (like byte size, signed/unsigned, integer/floating, etc.) converting a particular byte sequence into a number.


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