If you are working with TCP based protocols it can be very helpful to see the data from a TCP stream in the way that the application layer sees it. Perhaps you are looking for passwords in a Telnet stream, or you are trying to make sense of a data stream. Maybe you just need a display filter to show only the packets of that TCP stream. If so, Wireshark’s ability to follow a TCP stream will be useful to you.
Simply select a TCP packet in the packet list of the stream/connection you are interested in and then select the Follow TCP Stream menu item from the Wireshark Tools menu (or use the context menu in the packet list). Wireshark will set an appropriate display filter and pop up a dialog box with all the data from the TCP stream laid out in order, as shown in Figure 7.1, “The “Follow TCP Stream” dialog box”.
Opening the “Follow TCP Stream” applies a display filter which selects all the packets in the TCP stream you have selected. Some people open the “Follow TCP Stream” dialog and immediately close it as a quick way to isolate a particular stream.
The stream content is displayed in the same sequence as it appeared on the network. Traffic from A to B is marked in red, while traffic from B to A is marked in blue. If you like, you can change these colors in the “Colors” page if the “Preferences” dialog.
Non-printable characters will be replaced by dots.
The stream content won’t be updated while doing a live capture. To get the latest content you’ll have to reopen the dialog.
You can choose from the following actions:
You can choose to view the data in one of the following formats: