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I am seeing a "Malformed Packet" or an incorrect GSMTAP packet, while i am sending a GSM-SIM 11.11 packet over SIMtrace. I am generating the packet and I think it is valid. I am thinking that the problem is is caused because SIMtrace is using the gsmtap port 4729 and wireshark is waiting to see a GSMTAP packet, so maybe it is expecting a different lenght. I would like to learn what is wrong with the packets

I have an example on the pcap here:

Thanks for any ideas!

asked 30 Jun '14, 05:06

mozbery's gravatar image

accept rate: 0%

It seems like your tool is sending the decoding of the SIM command as plain text, which is definitely not what Wireshark (and the GSMTAP dissector) is expecting (we can see the decoding of the APDU in the ASCII part of the byte panel, while it should be an hex dump of the GSMTAP protocol). I guess you must be using the wrong command line when launching SIMtrace, and should ask for help on the osmocom mailing list.

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answered 30 Jun '14, 07:53

Pascal%20Quantin's gravatar image

Pascal Quantin
accept rate: 30%

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question asked: 30 Jun '14, 05:06

question was seen: 2,434 times

last updated: 30 Jun '14, 07:53

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