Re: [Mbm-devel] Modem-/NetworkManager support for modems not using PPP

[Torgny Johansson <torgny johansson gmail com>]

Hi Marius!

On Sat, Apr 16, 2011 at 2:57 PM, Marius Kotsbak
<marius kotsbak gmail com> wrote:
> Hi!
>
> There seems to be now quite a bit of modems appearing now that does not
> support the old method of using PPP protocol on the same tty device as
> the AT commands are sent, or it is not recommended for higher HSPA+ and
> LTE modems because of performance limitations of the PPP/tty layer.
> Those devices typically accept AT commands at one interface and use
> another interface for the network traffic (including first a DHCP query).
>
> One example is the Samsung GT-B3730 I'm currently developing drivers for:
>
> https://github.com/mkotsbak/Samsung-GT-B3730-linux-driver
>
> It seems to be the same case for LG VL600 4G (LTE):
>
> http://ubuntuforums.org/showpost.php?p=10589647&postcount=17
>
> https://github.com/balrog-kun/LG-VL600-utils
>
> The Ericsson Mobile Broadband Modules (I have an F5521gw based modem)
> seems to offer both the old ACM ports and support USB WCM / CDC NCM /
> CDC Ethernet protocols for higher performance:
>
> http://www.thinkwiki.org/wiki/Ericsson_F3507g_Mobile_Broadband_Module#Connecting_to_the_net_via_CDC_Ethernet_interface
>
> http://sourceforge.net/apps/mediawiki/mbm/index.php?title=MBM#Prerequisites
>
> http://cateee.net/lkddb/web-lkddb/USB_NET_CDC_NCM.html
>
> I wonder if support for this has been implemented or thought about in
> Modem-/NetworkManager. We probably need a flag for a modem manager
> module to tell that it does not use PPP and require to get IP address
> using DHCP instead.

Yes, support for using the cdc_ncm interface in ModemManger is already
available. The same goes for the older ericsson modules using the
cdc_ether interface. No need for PPP anymore.

You may have to add your vid/pid to the
/lib/udev/rules.d/77-mm-ericsson-mbm.rules
(.../plugins/77-mm-ericsson-mbm.rules if you have the MM sources
checked out) file to get ModemManager to recognize it (then run "sudo
udevadm control --reload-rules" and restart modemmanager).

Regards
Torgny