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Wireshark-dev: [Wireshark-dev] TCP segmentation loss

From: "Christopher White (WTA)" <christopher.white@xxxxxxxxxxxxxxxxx>
Date: Thu, 04 Jun 2009 09:28:46 +0200
Dear All,

I have recently been building a dissector for an 3GPP ASN.1 based
protocol which uses a tcp based transport.

I have followed the developer's guide (9.4) relating to the re-assembly
of fragments, and this seems to work fine.

However, after a tcp segment loss ( I have the preference analyse tcp
sequence no.  switched on), the ASN.1 BER PDUs are no longer detected
and decoded as expected. Somehow, synchronisation is lost. I presume
this is due to the sequence of segments on the wire.

I am new to building wireshark dissectors and with the ASN.1 tools. I
presume there is some additional logic required in my dissector - would
be very grateful if someone could point me in the right direction?

Best regards,
Chris