Hi.

> On 05.12.2014, at 06:42 , Pierre Rudloff <[email protected]> wrote:
> In the MLS Cell Netword Export Data, there are around 1800 cells with
> the MCC code 208 and the MNC code 165.
> But this code does not exist in the official list maintained by the ITU:
> http://www.itu.int/dms_pub/itu-t/opb/sp/T-SP-E.212B-2014-PDF-E.pdf
> 
> Do you have any idea what this could be?

We are tracking this in https://github.com/mozilla/ichnaea/issues/340

It looks like it's an encoding error happening in the radio drivers on some 
phones. Those are famous for being buggy and getting hexadecimal vs. decimal 
values wrong.

The other part to this is, that there are some mobile networks codes that 
aren't assigned globally but instead by local numbering authorities. One 
example of this are Tetra networks which have a GSM-compatibility mode.

So for now we don't use the ITU list as a whitelist, but instead just do a 
simple range check and accept all mnc values in the 1 to 999 range. This might 
lead to some invalid networks ending up in our database, but only buggy devices 
should ask for those for positioning purposes, so it doesn't worsen the quality 
for the majority of users.

Hanno
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