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6 <title>Petter Reinholdtsen: Visualizing GSM radio chatter using gr-gsm and Hopglass</title>
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14 <h1>
15 <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
16
17 </h1>
18
19 </div>
20
21
22 <div class="entry">
23 <div class="title">Visualizing GSM radio chatter using gr-gsm and Hopglass</div>
24 <div class="date">29th September 2017</div>
25 <div class="body"><p>Every mobile phone announce its existence over radio to the nearby
26 mobile cell towers. And this radio chatter is available for anyone
27 with a radio receiver capable of receiving them. Details about the
28 mobile phones with very good accuracy is of course collected by the
29 phone companies, but this is not the topic of this blog post. The
30 mobile phone radio chatter make it possible to figure out when a cell
31 phone is nearby, as it include the SIM card ID (IMSI). By paying
32 attention over time, one can see when a phone arrive and when it leave
33 an area. I believe it would be nice to make this information more
34 available to the general public, to make more people aware of how
35 their phones are announcing their whereabouts to anyone that care to
36 listen.</p>
37
38 <p>I am very happy to report that we managed to get something
39 visualizing this information up and running for
40 <a href="http://norwaymakers.org/osf17">Oslo Skaperfestival 2017</a>
41 (Oslo Makers Festival) taking place today and tomorrow at Deichmanske
42 library. The solution is based on the
43 <a href="http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html">simple
44 recipe for listening to GSM chatter</a> I posted a few days ago, and
45 will show up at the stand of <a href="http://sonen.ifi.uio.no/">Ă…pen
46 Sone from the Computer Science department of the University of
47 Oslo</a>. The presentation will show the nearby mobile phones (aka
48 IMSIs) as dots in a web browser graph, with lines to the dot
49 representing mobile base station it is talking to. It was working in
50 the lab yesterday, and was moved into place this morning.</p>
51
52 <p>We set up a fairly powerful desktop machine using Debian
53 Buster/Testing with several (five, I believe) RTL2838 DVB-T receivers
54 connected and visualize the visible cell phone towers using an
55 <a href="https://github.com/marlow925/hopglass">English version of
56 Hopglass</a>. A fairly powerfull machine is needed as the
57 grgsm_livemon_headless processes from
58 <a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a> converting
59 the radio signal to data packages is quite CPU intensive.</p>
60
61 <p>The frequencies to listen to, are identified using a slightly
62 patched scan-and-livemon (to set the --args values for each receiver),
63 and the Hopglass data is generated using the
64 <a href="https://github.com/petterreinholdtsen/IMSI-catcher/tree/meshviewer-output">patches
65 in my meshviewer-output branch</a>. For some reason we could not get
66 more than four SDRs working. There is also a geographical map trying
67 to show the location of the base stations, but I believe their
68 coordinates are hardcoded to some random location in Germany, I
69 believe. The code should be replaced with code to look up location in
70 a text file, a sqlite database or one of the online databases
71 mentioned in
72 <a href="https://github.com/Oros42/IMSI-catcher/issues/14">the github
73 issue for the topic</a>.
74
75 <p>If this sound interesting, visit the stand at the festival!</p>
76 </div>
77
78 <div class="tags">Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.</div>
79
80
81 </div>
82
83
84
85
86 <div id="sidebar">
87
88
89
90 <h2>Archive</h2>
91 <ul>
92
93 <li>2017
94 <ul>
95
96 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/01/">January (4)</a></li>
97
98 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/02/">February (3)</a></li>
99
100 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/03/">March (5)</a></li>
101
102 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/04/">April (2)</a></li>
103
104 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/06/">June (5)</a></li>
105
106 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/07/">July (1)</a></li>
107
108 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/08/">August (1)</a></li>
109
110 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/09/">September (3)</a></li>
111
112 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/10/">October (2)</a></li>
113
114 </ul></li>
115
116 <li>2016
117 <ul>
118
119 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/01/">January (3)</a></li>
120
121 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/02/">February (2)</a></li>
122
123 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/03/">March (3)</a></li>
124
125 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/04/">April (8)</a></li>
126
127 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/05/">May (8)</a></li>
128
129 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/06/">June (2)</a></li>
130
131 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/07/">July (2)</a></li>
132
133 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/08/">August (5)</a></li>
134
135 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/09/">September (2)</a></li>
136
137 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/10/">October (3)</a></li>
138
139 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/11/">November (8)</a></li>
140
141 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/12/">December (5)</a></li>
142
143 </ul></li>
144
145 <li>2015
146 <ul>
147
148 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
149
150 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
151
152 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
153
154 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
155
156 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/05/">May (3)</a></li>
157
158 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/06/">June (4)</a></li>
159
160 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/07/">July (6)</a></li>
161
162 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/08/">August (2)</a></li>
163
164 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/09/">September (2)</a></li>
165
166 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/10/">October (9)</a></li>
167
168 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/11/">November (6)</a></li>
169
170 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/12/">December (3)</a></li>
171
172 </ul></li>
173
174 <li>2014
175 <ul>
176
177 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
178
179 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
180
181 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
182
183 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
184
185 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
186
187 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
188
189 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
190
191 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
192
193 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
194
195 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
196
197 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
198
199 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
200
201 </ul></li>
202
203 <li>2013
204 <ul>
205
206 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
207
208 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
209
210 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
211
212 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
213
214 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
215
216 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
217
218 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
219
220 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
221
222 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
223
224 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
225
226 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
227
228 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
229
230 </ul></li>
231
232 <li>2012
233 <ul>
234
235 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
236
237 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
238
239 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
240
241 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
242
243 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
244
245 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
246
247 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
248
249 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
250
251 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
252
253 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
254
255 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
256
257 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
258
259 </ul></li>
260
261 <li>2011
262 <ul>
263
264 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
265
266 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
267
268 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
269
270 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
271
272 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
273
274 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
275
276 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
277
278 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
279
280 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
281
282 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
283
284 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
285
286 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
287
288 </ul></li>
289
290 <li>2010
291 <ul>
292
293 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
294
295 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
296
297 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
298
299 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
300
301 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
302
303 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
304
305 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
306
307 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
308
309 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
310
311 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
312
313 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
314
315 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
316
317 </ul></li>
318
319 <li>2009
320 <ul>
321
322 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
323
324 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
325
326 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
327
328 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
329
330 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
331
332 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
333
334 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
335
336 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
337
338 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
339
340 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
341
342 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
343
344 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
345
346 </ul></li>
347
348 <li>2008
349 <ul>
350
351 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
352
353 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
354
355 </ul></li>
356
357 </ul>
358
359
360
361 <h2>Tags</h2>
362 <ul>
363
364 <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (14)</a></li>
365
366 <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
367
368 <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
369
370 <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
371
372 <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (9)</a></li>
373
374 <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (16)</a></li>
375
376 <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
377
378 <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
379
380 <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (154)</a></li>
381
382 <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (158)</a></li>
383
384 <li><a href="http://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook (4)</a></li>
385
386 <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
387
388 <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (17)</a></li>
389
390 <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (24)</a></li>
391
392 <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
393
394 <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (354)</a></li>
395
396 <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
397
398 <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
399
400 <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (30)</a></li>
401
402 <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
403
404 <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (18)</a></li>
405
406 <li><a href="http://people.skolelinux.org/pere/blog/tags/h264">h264 (20)</a></li>
407
408 <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (42)</a></li>
409
410 <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (15)</a></li>
411
412 <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (20)</a></li>
413
414 <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
415
416 <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
417
418 <li><a href="http://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
419
420 <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
421
422 <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
423
424 <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (39)</a></li>
425
426 <li><a href="http://people.skolelinux.org/pere/blog/tags/nice free software">nice free software (9)</a></li>
427
428 <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (293)</a></li>
429
430 <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (189)</a></li>
431
432 <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (33)</a></li>
433
434 <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
435
436 <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (64)</a></li>
437
438 <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (104)</a></li>
439
440 <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
441
442 <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
443
444 <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
445
446 <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
447
448 <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (10)</a></li>
449
450 <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
451
452 <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (5)</a></li>
453
454 <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
455
456 <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (53)</a></li>
457
458 <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
459
460 <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (5)</a></li>
461
462 <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (55)</a></li>
463
464 <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (6)</a></li>
465
466 <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (12)</a></li>
467
468 <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (52)</a></li>
469
470 <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (3)</a></li>
471
472 <li><a href="http://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
473
474 <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (9)</a></li>
475
476 <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (59)</a></li>
477
478 <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
479
480 <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (40)</a></li>
481
482 </ul>
483
484
485 </div>
486 <p style="text-align: right">
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