GSM Modem Confusion

Harald Welte laforge at
Sat Jul 28 05:49:18 CEST 2007

On Wed, Jul 18, 2007 at 11:11:16PM -0400, Wally Ritchie wrote:
> So it is with calypso based neo1973. I think we have here a
> good starting point with as near a complete 7.07/7.10 implementation
> as is possible consistent with other requirements.
> As for the "modem". IMHO the word "gsm modem" should be reserved for
> what gsmd provides to external TE e.g. as a laptop, PC, or PDA, that
> uses a neo1973 for gprs or hcsd access. This is another 7.07 (possibly
> even with a 7.10 layer) interface accessed through Bluetooth (or irda,
> or usb serial). It would be less confusing if we didn't refer to
> the calpyso 7.07/7.10 as a modem (perhaps chipset instead).

unfortuantely that is not our strategy.  Your view seems to be heavily
influenced by years (decades?) of experience in mobile phone
development.  But we're not coming from a mobile phone point of view.

You see, what we are trying to build here is not something that
technically resembles 'yet another cellphone', but what we're building
are open source linux-based mobile communications devices.

We have no interest to support an AT command interface to any external
entity outside of our devices, at least certainly not for another 12
months, if not beyond that.

Similarly, we don't have any intention to implement MMS, WAP, WML, etc.

So to us, GSM in the mobile communications device (which we actually
don't call a phone ourselves!) is a technology to provide one particular
(minor) feature such a GSM voice calls, and to provide IP access over
GPRS (and later 3G).

If somebody wants to provide internet access to another device (i.e. his
laptop), our strategy is to do this via USB ethernet, BNEP or even WiFi.

The Neo becomes your portable access point, to which you talk TCP/IP.

So this requirement for 'another 7.07 layer' really doesn't exist on our

- Harald Welte <laforge at>         
Software for the world's first truly open Free Software mobile phone

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