MS basic connect extensions: 0d3a or 9d3a?

Bjørn Mork bjorn at
Mon Sep 10 15:49:33 UTC 2018

Ben Chan <benchan at> writes:

> Looks like Microsoft uses inconsistent UUIDs for the same MS basic connect
> extensions:
> :
> Service UUID = 3d01dcc5-fef5-4d05-9d3a-bef7058e9aaf
> :
> UUID Value = 3d01dcc5-fef5-4d05-0d3a-bef7058e9aaf
> I added the extensions based on the PCO CID.   Given the close resemblance
> of these two UUIDs, it looks more like a typo in their doc.  I tested with
> Fibocom L850, which supports the PCO CID and uses the 9d3a variant.
>  Unfortunately, I don't have another modem to compare with.

Well, we can always look it up in the MBIM registry at

Oh, wait, I forgot - no one cares about maintaining that.  There's not a
single Intel entry for example, despite their role in the USB-IF.  So I
completely understand that Microsoft stopped bothering as well.  At
least they have the decency to document their stuff to the public.


More information about the libmbim-devel mailing list