SIM ICCID with invalid character 'C'

[Andrew Bird]

On Wed, 27 Dec 2017 22:09:25 +0100
Aleksander Morgado <aleksander at aleksander.es> wrote:

> Hey,
> 
> It looks like there are SIMs out there that report an ICCID that is
> not read correctly by ModemManager:
> 
>  <debug> [1514406745.769547] (ttyACM2): --> 'AT+CRSM=176,12258,0,0,10<CR>'
>  <debug> [1514406745.797843] (ttyACM2): <-- '<CR><LF>+CRSM:
> 145,15,"9868200C214365870921"<CR><LF><CR><LF>OK<CR><LF>
>  <warn>  [1514406745.798699] couldn't load SIM identifier: 'ICCID
> response contained invalid character 'C''
> 
> Once processed the ICCID would have been reported as:
>   898602C0123456789012
> 
> i.e.:
>   89: telecom
>   86: china:
>   02: cmcc (operator)
>   character C
>   012345678901: 12 digits with the account number, operator-specific format
>   2: check digit, I assume
> 
> At the end, this could be a valid 19-digit ICCID, but normally we
> would have seen this with a 'F' character as padding, not a 'C'
> character in the middle separating the issuer code and the account
> number.
> 
> What should we do with this? should we for example, allow having
> 19-digit ICCIDs that may include an additional character anywhere to
> form the 20-digit value we read from the SIM?
> 
> 
> -- 
> Aleksander
> https://aleksander.es
> _______________________________________________
> ModemManager-devel mailing list
> ModemManager-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/modemmanager-devel
> 

It looks like there are plans(2017) to change the format of ISO/7812 allowing an 8 digit IIN at the expense of the account number. I suspect you'll need to get hold of that spec, though I don't beleive it's available for free. See https://en.wikipedia.org/wiki/ISO/IEC_7812 for an overview.

Andrew


-- 
Andrew Bird <ajb at spheresystems.co.uk>