Hi all,

First time post.

I'm developing a java based app that uses tshark as the underlying capture  
mechanism.  I set up tshark and set capture filters and output the data in  
PDML format (which is captured via stdin in my Java app and parsed via  
SAX).

I've created a stream manager that holds stream objects.  Each stream  
contains all packets belonging to the communication between a client and  
server i.e. each packet sent between the client/server for any one TCP  
Stream.

For the purpose of this mail I'm targetting HTTP.

I capture all TCP packets and add them to the appropriate stream.  When I  
come across a HTTP message I add this to the same stream.  In my capture  
file that I use for testing I have HTTP request and HTTP response.  So the  
first 3 packets are those of the TCP handshake (SYN, SYN_ACK and ACK).   
The fourth packet would normally be the HTTP request but due to the fact  
the segments are split up and then reassembled I actually have four extra  
TCP packets that I don't need (yes I know they are needed but I only want  
the reassembled one). Here are some packet details

Handshake
---------
1. SYN from Client
2. SYN_ACK from Server
3. ACK from Client

Extra packets
-------------
4. RST_ACK from Client
5. ACK from Client (TCP segment of a reassembled PDU)
6. ACK from Client (TCP segment of a reassembled PDU)
7. PSH_ACK from Client (TCP segment of a reassembled PDU)

HTTP Request
------------
8. PSH_ACK HTTP Request from Client (POST method)

 From what I understand that PDUs can be split across segments for two main  
reasons:
1. Some packets are missing (not in my case)
2. Size of info based on segment means it has to be split

I need the fact wireshark can reassemble the data into another packet so  
I'm not willing to turn reassembly off.

I dont want to see the extra TCP segment packets in my PDML stream, only  
the reassembled ones.  Is there a filter (capture or display) that I can  
set with t-shark to omit the segment packets from my PDML stream (remember  
I use Wireshark for visual analysis of the data but tshark in my java app?

Thanks in advance,
JP

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