Huge thanks to our Platinum Members Endace and LiveAction,
and our Silver Member Veeam, for supporting the Wireshark Foundation and project.

Wireshark-users: [Wireshark-users] Method to accomplish the equivalent of "http.content_length >

From: Marc Reynolds <mwreynolds@xxxxxxxxx>
Date: Thu, 19 Oct 2006 23:14:38 +0000 (UTC)
I have a periodic need to identify object downloads in http traces. This is 
easily accomplished by setting the display filter (http.response.code == 200).

Some traces, however, may contain large numbers of tiny and (for my purposes) 
inconsequential objects, so I would like to be able to additionally apply 
something like (http.content_length > nnnn) to return only the larger 
reassembled objects.

This does not work, however, because (I believe) that Wireshark treats the 
value of http.content_length as a string, not an integer, so the "greater-than" 
functionality does not apply. Interestingly, the filter editor / syntax checker 
does let me build and apply such a filter, but the results seem random, 
returning a mix of http 200 frames whose content lengths are larger and smaller 
than the value of nnnn.

Is there a way to accomplish what I am trying to do? Is there a reason that 
greater-than is allowed on non-numerical fields? Is there some way to leverage 
this which I am not seeing?

Alternatively, is there any other way to accomplish something similar? For 
example, it would be great if there were a way to accomplish something 
logically similar to (tcp.reassemble_size > nnnn).

The latter approach would actually be useful in several other cases I can think 
of, as well.

Thanks in advance for any insights.