Re: Fix for Telstra 4G USB Modem

On 2/28/2013 12:10 PM, Arion Blishen wrote:
> I found a way to get the Telstra 4G USB Modem to work with IPCop. The
> model I have is ZTE MF821 there is also a post paid model Sierra 320U
> which should be able to work the same just has different USB IDs

You say nothing of which version of IPCop you are using. If 2.x, did the 
built in usb mode change program that uses udev NOT work by simply 
plugging the device in and not automatically load a suitable usbserial 
driver from the kernel? A lot of work was put into this very feature 
prior to IPCop 2.0.0's release.

> I used the instructions in
>
> http://www.eigenmagic.com/2012/03/14/how-to-get-telstra-4g-mobile-broadband-working-with-linux/
>
> Also see this thread
>
> http://forums.whirlpool.net.au/forum-replies.cfm?t=2060627&p=-1
>
> but I have to run
>
> modprobe usbserial
>
> as the /dev/ttyUSB0 etc are not created automatically on boot or at any time

I just looked up the values and they are in recent udev modeswitch rules 
as of IPCop 2.0.6 and possibly earlier:

# ZTE MF820 4G LTE
ATTRS{idVendor}=="19d2", ATTRS{idProduct}=="0166", RUN+="usb_modeswitch 
'%b/%k'"

If you unplug the modem on a running system and plug it back in what 
happens? Unfortunately modeswitch doesn't seem to get it out of cdrom 
mode during boot, at least on some systems such as mine and the 
usbserial related driver will NOT load in cdrom mode. I added this to my 
/etc/rc.d/rc.event.local to get around the boot limitation:

/usr/sbin/usb_modeswitch -v 0x19d2 -p 0x2000 -m 0x01 -M 
"5553424312345679000000000000061b000000020000000000000000000000"

This gets it out of cdrom mode and the proper driver loads automatically 
for my hardware per the above example. If the system is up and running 
already, unplugging the modem and plugging it back in works 
automatically via modeswitch and subsequent usbserial driver load once 
the switch takes place. In other words, usb modeswitch in IPCop works 
perfectly on a running system.
>
> Also any chance that QMI WWAN driver support can be added to IPCop. This
> makes the USB Modems run as a network interface rather than using PPP
> and is much faster as PPP is limited to 25Mbit
>

The QMI WWAN driver will only activate the ethernet part of the chips 
and will still require much configuration to be usable since you still 
need to control the cellular data end via Hayes AT commands pointed to a 
usbserial type device node. I'd rather just skip the foofala and 
communicate directly to the node via the ppp dialer as we do now. Fake 
ethernet drivers on cellular data devices go back years but is not all 
the rage for good reason. Still, it's up to the devs if they want to 
incorporate it into IPCop.

Where did you get the 25mbs figure for ppp? My connection using dialup 
is 42mbs between me and my tower using a tmobile rocket card and the 
42mbs is a moot point since I and everyone else connected to that tower 
use the same network backhaul to the tower putting it right in oversold 
cable internet territory where you share the same pipe with over 100 
other people, probably 1000 in this case. I have yet to break 10mbs even 
at 4am even though I connect to the tower at 42mbs as I said earlier 
which has nothing to do with ppp. Seems as if nobody considers the 
backhaul to the tower which could be the data equivalent of a goat trail 
for all we know.

In your case as usually is the case, it's all a matter of having the 
right AT wordstring to get the most out of it, ie, the so called 4G mode.

As far as 4G versus 3G, well, according to the ITU, anything below 
160mbs in the download direction for wireless data is NOT 4G, call it 
infinite G if it makes you feel better. In other words, cellular 
carriers went overboard in advertising, once one lied, the others wound 
up following suite rather than disputing the first liar's 
disinformation. The ITU seems to have thrown it's hands in the air once 
this got out of hand. Lies and damned lies. What? From cellular 
carriers? Say it isn't so!

-- 
Dave Studeman
http://www.raqcop.com


------------------------------------------------------------------------------
Everyone hates slow websites. So do we.
Make your web apps faster with AppDynamics
Download AppDynamics Lite for free today:
http://p.sf.net/sfu/appdyn_d2d_feb