It is often very useful to observe the packets that flow in and out of each of the two Maxwell interfaces.  The easiest way to do this is to use a tool called Wireshark.  Wireshark is a network analysis application that can capture, display, and save packets.

Maxwell has two data interfaces, so the way to view packets is to run two instances of Wireshark, one viewing one interface the other viewing the other interface.

Your Maxwell may have a Wireshark icon on the desktop.  If so, you can launch one or more instances of Wireshark by clicking on that icon.  If you don't have an icon you can find Wireshark under the "Internet" submenu of the K-menu (which is found via the square blue icon at the very lower left corner of the desktop toolbar at the bottom of the screen.)

Maxwell automatically works with Wireshark; you do not need to do anything special with Maxwell.

Wireshark may ask for the root password.  It needs this to obtain access to the raw packet data of the network interfaces.

The Maxwell GUI tells you which interfaces Maxwell is using.  Depending on your version of Maxwell code this information may be visible via the information window of the Maxwell launcher application (this is the one that asks "What do you want to do?") or, for newer versions, under the "System" portion of the Maxwell graphical user interface.

Once you launch the two copies of wireshark you will need to configure them so that one Wireshark uses one of the interfaces and the other Wireshark uses the other.  This is done via the "Interfaces" and "Options" items under Wireshark's "Capture" menu.

Wireshark can consume a significant amount of computer resources, especially when the network is carrying a lot of traffic.  So some care should be taken when running Wireshark with Maxwell.  In particularly, Wireshark should be used only when needed.