Wireshark-users: Re: [Wireshark-users] Understand wireshark data

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Fri, 21 Aug 2009 16:25:26 -0700

On Aug 19, 2009, at 8:09 AM, deostroll@xxxxxxxxx wrote:

Hi. Okay I have captured data with wireshark. I am trying to understand telnet commands to send to my telnet server. (You know things like IAC, DO, WILL WONT, etc).

For one packet, in the packet details window under the node "Telnet" node I saw something written like:

Command: Will Terminal Type
Command: Will Negotiate About Window Size

Does this translate to

IAC WILL [Terminal Type] IAC WILL SB [Window size]

Yes.

One could argue that, underneath the "Command: XXX" entries, there should be subitems for the IAC byte, the command byte, and the arguments to the command.

Is it one sequence of instruction or two instructions?


It's two commands, in the sense that there are two Interpret As Command bytes. It's also a sequence of bytes containing those two commands.