Re: [ANNOUNCE] ModemManager (for GSM and CDMA)

["Tambet Ingo" <tambet gmail com>]

On Sat, Aug 2, 2008 at 2:43 PM, Stuart Ward <stuart ward bcs org> wrote:
> The whole point of Network Manager is that it is the integrated network
> access tool. Modems are largely standard. we don't need special software to
> access different modems. Perhaps we need a configuration strings for some
> modems but I see no point in having a separate tool for modems.
>
> Equally for GSM modems these are as least as standardised as WiFi cards. So
> we should not need a seperate tool to manage them.
>
> What Network Manager should show is the GSM signal strength as soon as you
> plug in a modem, and allow a button to select and establish the connection.
> Just like the WiFi selection.
>
> Am I missing something here?

This is just a code reorganization, the NetworkManager will still be
the frontend for everything. There are no UI or work flow changes
caused by this. As I've tried to explain multiple times already, the
reorganization was done mainly to support other modem backends that
are currently more advanced than what NM has.

Modems are very much _not_ standardized for anything except the very
basic functionality. Your example (signal strength) is a good one:
while not connected, NM does not keep the serial device open just to
get the signal strength. While connected through modem though, it
depends very much on modem hardware how to do it: Some cards have
another serial device for monitoring (some use binary format there,
some use AT commands with different formats), some have one
multiplexed device. So there needs to be different handling for
different cards and providing a plugins framework in ModemManager is
exactly for this.

The big difference between wifi and modems is that wifi scanning takes
less than a second, so we can schedule scans in some intervals. For
modems though, scanning takes a long time (over 10 seconds, sometimes
even close to a minute for cards which support a wide range of
frequencies), so NM can not just randomly block the access to modem
for such long periods of time.

Tambet