Check ARFCN for use from the right provider

[Gitschubser]

Add a check if the ARFCN from the serving cell and the neighbouring cells are from the correct provider. For this we need/must collect the data for all providers.

Example for Germany:

User	GSM 900	DCS 1800	Number of channels GSM 900 / DCS 1800
D1 / Telekom	13–49, 81–102, 122–124	587–611	62 / 25
D2 / Vodafone	1–12, 50–80, 103–121	725–751	62 / 27
E1 / E-Plus	975–999	777–863	25 / 87
E2 / O₂	1000–1023, 0	637–723	25 / 87
Deutsche Bahn	55–974		20 / -

Richard Schwab

Source: Wikipedia

If there is a cellid/neighbouring cell with the arfcn 726 from the provider o2 there could be something not correct.

[E3V3A]

@Gitschubser Hi, thanks for that useful info, but how can we find out what ARFCNs all providers are using? Surely there should be a DB somewhere or something else? (How did you find your list?) Also are these "globally" allocated or would different countries have different policies. Meaning, could there exists a country X that perhaps does not care to allocate ARFCNs at all?

@xLaMbChOpSx Can you add this field to our Cell DB? I guess from the above, that this info should be a text-field consisting of a CSV separated list of values, sometimes a range of values, for each Cell provider. I'm not sure how the DB tables look as of today, so perhaps you can post a Gist entry with the latest DB table layouts?

[E3V3A]

@xLaMbChOpSx Ignore that. Let's not add more stuff to DB before we know we actually need it. Besides the ARFCNs are different (and the whole thing get more complicated) for different network types.

[Gitschubser]

The source from the ARFCN is: http://de.wikipedia.org/wiki/Global_System_for_Mobile_Communications#Verwendete_Frequenzen We can find out what ARFCNs are used if we store this in a database and analyze the data.

[E3V3A]

I don't know why that table is so damn hard to fix. I tried found this: https://github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet

[SecUpwN]

@E3V3A, already tried to fix the table in the OP multiple times. Seems like GitHub is mocking around, usually the type of table you see in the OP works perfectly, but here it doesn't. That's why I added the "```" markings - that way we can at least read that damn table properly.

[Nothing4You]

You can do

User	GSM 900	DCS 1800	Number of channels GSM 900 / DCS 1800
D1 / Telekom	13–49, 81–102, 122–124	587–611	62 / 25
D2 / Vodafone	1–12, 50–80, 103–121	725–751	62 / 27
E1 / E-Plus	975–999	777–863	25 / 87
E2 / O₂	1000–1023, 0	637–723	25 / 87
Deutsche Bahn	55–974		20 / -

|      User     |          GSM 900       | DCS 1800 | Number of channels <br/> GSM 900 / DCS 1800     |
|:------------- |:---------------------- |:-------- | ------------------:|
| D1 / Telekom  | 13–49, 81–102, 122–124 | 587–611  | 62 / 25            |
| D2 / Vodafone | 1–12, 50–80, 103–121   | 725–751  | 62 / 27            |
| E1 / E-Plus   | 975–999                | 777–863  | 25 / 87            |
| E2 / O₂       | 1000–1023, 0           | 637–723  | 25 / 87            |
| Deutsche Bahn | 55–974                 |          | 20 / -             |

[Nothing4You]

Actually, I need to correct myself.

I just learned that github also accepts HTML, so with a simple <br/> you can add a linebreak, updated my previous comment.

[SecUpwN]

Perfect. Thank you, @Nothing4You! I've updated the OP. :+1:

[andr3jx]

I suggest to close this issue. Look at this presentation, page 26. It is common practice that IMSI-Catchers use legit ARFCN to force the mobile station to connect.

[E3V3A]

Thank you @andr3jx. Issue closed and marked as invalid.