Lucent Technologies Ethereal - Manual (Page 163)

9.4. Control Protocol dissection
The user can control how protocols are dissected.
Each protocol has its own dissector, so dissecting a complete packet will typically involve several
dissectors. As Ethereal tries to find the right dissector for each packet (using static "routes" and
heuristics "guessing"), it might choose the wrong dissector in your specific case. For example, Eth-
ereal won't know if you use a common protocol on an uncommon TCP port, e.g. using HTTP on
TCP port 800 instead of the standard port 80.
There are two ways to control the relations between protocol dissectors: disable a protocol dissector
completely or temporarily divert the way Ethereal calls the dissectors.
9.4.1. The "Enabled Protocols" dialog box
The Enabled Protocols dialog box lets you enable or disable specific protocols, all protocols are en-
abled by default. When a protocol is disabled, Ethereal stops processing a packet whenever that pro-
tocol is encountered.
Note!
Disabling a protocol will prevent information about higher-layer protocols from being
displayed. For example, suppose you disabled the IP protocol and selected a packet
containing Ethernet, IP, TCP, and HTTP information. The Ethernet information would
be displayed, but the IP, TCP and HTTP information would not - disabling IP would
prevent it and the other protocols from being displayed.
Figure 9.5. The "Enabled Protocols" dialog box
Customizing Ethereal
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