Ethereal-dev: [Ethereal-dev] sample file for GSM frames
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Hi
I am trying to analyse some GSM layer-2
frames that I extracted from my mobile phone.
The problem is that they don't have
the right header.
If I understand correctly, Ethereal
needs the frame to be inside TCP-IP encapsulation, probably also inside
something called MCU2 or similar.
But this doesn't apply to GSM, so I would need someone to embed my GSM
inside a frame that Ethereal can understand.
I suppose the developpers for the gsm_map
dissector have such examples, so if you can send me an example file, it
will be perfect for me.
Thanks
Francisco
for example, this is one of my frames:
25 06 21 00 05 f4 64 11 77 9e 2b 2b
2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b
25 001001-- Pseudo length
: 9
------01 Flag
06 0------- direction from
: originating site
-000---- TransactionID
: 0
----0110 Protocol
Discrim. : radio resource management messages
21 00100001 MESSAGE TYPE
: PAGING REQUEST TYPE 1
00 ----00-- spare bits
: 0
------00 Page Mode
: Normal paging
--00---- Channel
Needed : (first) Any Channel
00------ Channel
Needed : (second) Any Channel
: Mobile Identity 1
05 00000101 length of Mob.ident.:
5
f4 1111---- Identity Digit
1 : hex value = f, if TMSI/P-TMSI
----0--- No. of
ID digits : even
-----100 Type of
identity : TMSI/P-TMSI
64 01100100 Identity Digit
2,3 : take hex value
11 00010001 Identity Digit
4,5 : take hex value
77 01110111 Identity Digit
6,7 : take hex value
9e 10011110 Identity Digit
8,9 : take hex value