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Wireshark-dev: [Wireshark-dev] Dissector for H1 protocol not called

From: Thomas Boehne <TBoehne@xxxxxxxx>
Date: Thu, 20 Jul 2006 10:46:30 +0200
Hello,

I was capturing H1 traffic, and for some TCP port combinations the H1
dissector was called for other combinations the generic "data"
dissector was used. Can somebody tell me why? I thought the
packet-h1.c dissector would dissect all packets that start with "S5",
but apperently the dissector is not called at all for some packets
(see attached files H1-ok.pcap and H1-nok.pcap). If I manually change
the ports in H1-nok.pcap, the dissector is called.

When exactly is the "data" dissector used? I thought it would be some
kind of fall back dissector for packets which no other dissector can
dissect, but apparently it is sometimes used before other dissectors
are checked.

The problem is occurs both in 0.99.2 and current SVN.

Best regards,
Thomas Böhne

-- 
Jäger Computergesteuerte Messtechnik GmbH
Thomas Böhne
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64653 Lorsch
Germany
Phone: +49-6251-9632-0


Attachment: H1-nok.pcap
Description: Binary data

Attachment: H1-ok.pcap
Description: Binary data