Re: Roaming network selection with MB

[Rick Jones <rick activeservice co uk>]

--On Wednesday, July 01, 2009 08:38:21 -0400 Dan Williams <dcbw redhat com> wrote:

¦ On Wed, 2009-06-10 at 13:07 +0100, Rick Jones wrote:

¦ > I discovered that my carrier only has roaming agreements with 2 of the
¦ > 3 French networks, but this doesn't stop the modem locking onto the
¦ > wireless signal of the unsupported one (it's not barred in the SIM).
¦ > This requires manual selection of the network before attempting to
¦ > make a connection. Their Windows connection gadget supports this - is
¦ > this a feature that will be available in Modem Manager?
¦ 
¦ The "Network" field of the 3G connection editor window for your
¦ connection will accept an MCC/MNC value like "31026" which identifies a
¦ specific network to register with, and no others.  You can use that to
¦ lock to the network you want, but then you can't roam.

Useful to know, although could be a bit limiting.

¦ With modem-manager, we could, if manual registration fails, do a
¦ scan (which can take up to 2 or 3 minutes unfortunately depending on how
¦ many bands your modem supports, anywhere from 2 to 8).  Then we could
¦ pick a provider out of the scan that you've explicitly allowed roaming
¦ to, or something like that.

That would be a good feature - in fact I would say essential. That's what the proprietary Windows connection gadget does, and I've managed a crude version using shell scripts that just echo AT commands and read the responses. At the moment that does the job, although it's not very pretty! A scan usually takes around 15-20 secs, but I've arranged it so that once I know the network number I can just enter that without waiting for the scan.

[ another bizzare ZTE quirk: the name of my network in the UK is "3", that's the brand. Using AT+COPS you can select network by name or number, but if you select by name and pass "3" as the name, the modem firmware interprets it as a number, even if it's in quotes - and ignores it. Thus you can only select the "3" network by its network number - aarrgh! ]

Cheers, Rick