Mobile Broadband - Why so tricky?

[viking777]

Since the release of Mint 8 there have been a number of posts about problems with mobile broadband modems, I have had problems with them myself. The point of this post is not to try and solve these problems but to illustrate what a potential minefield it is. (Incidentally my 'solution' to this problem is here: http://forums.linuxmint.com/viewtopic.p ... 48#p209495 but although this mostly works for me it doesn't work for everyone)

Over the years I have collected 3 different modems (Huawei E220, Huawei K3565 and ZTE 622), and at the present moment in time I have access to 7 different distributions, so I thought I would 'compare and contrast', and this is the result. (I tried to tabulate it, but I don't see a way to post tables on the forum so if you want to read it then it will have to be as it is!)

EDIT. Just got access to suse 11.2 and added that to the list. Interesting to compare it with 11.1. On 11.1 all modems work on 11.2 (later kernel) only 2 work - the same two that work on the Mandriva Live CD which uses a similar kernel.


PCLinuxOS - kernel 2.6.26.8 - usb-modewsitch not required - All 3 modems work.

Crunchbang Lite - kernel 2.6.26-13 - usb-modewsitch not required - All 3 modems work.

Slax Live CD - kernel 2.6.27.27 - usb modeswitch not required - All 3 modems work

OpenSuse11.1 Live CD - kernel 2.6.27.29 - usb-modeswitch not required - All three modems work.

Mint7 - kernel 2.6.28.17 - requires usb-modeswitch - All 3 modems work. See Edit below.

Mandriva2010 Live CD - kernel 2.6.31.2 - usb-modeswitch may be required - E220 and K3565 work, ZTE doesn't work but may do if I installed 'modeswitch' which I haven't tried (not much point on a live CD)

OpenSuse11.2 Live CD - kernel 2.6.31.5 - usb-modeswitch may be required - E220 and K3565 work ZTE doesn't work but may do if I installed 'modeswitch' which I haven't tried (not much point on a live CD)

Fedora 12 - kernel 2.6.31.5 - K3565 works, ZTE and E220 doesn't work (with or without usb-modeswitch)

Mint8 - kernel 2.6.31.16 - requires usb-modeswitch - ZTE and K3565 work, E220 doesn't.

Ubuntu9.10 - kernel 2.6.31.16 - requires usb-modeswitch - ZTE and K3565 work, E220 doesn't.

Sidux - kernel 2.6.32-0.slh2 - requires usb-modeswitch - All 3 modems work.

Ubuntu 10.04alpha2 - kernel 2.6.32.4 - not tested with usb-modeswitch - K3565 works, ZTE and E220 doesn't (suspect ZTE would work with modeswitch)


Conclusions?
Difficult. I might conclude that the older kernels (2.6.26 and 2.6.27) are better as Opensuse and Pclinux both work 'unaided' as it were so maybe that is a kernel regression. On the other hand I have read of some people having success just by installing the 2.6.32 kernel (though it doesn't work for me without 'modeswitch')


The real conclusion is this. I only have access to 3 modems, there are probably 20 times that many in production/use right now, I have access to only one computer there are millions out there, and I have access to only 7 distros and there are 100 or more out there. So the disparity in results that I get will be magnified many times over in everyday use 'in the wild'. Add to that the fact that mobile broadband is still very much a 'minority' interest compared to wireless or ethernet, and I guess you get the answer to the question I posed in the title.

I am not defending that position though, I would like it to work as much as the next man.

EDIT. A recent experiment (16 Jan 2010) with Mint 7 has led to the conclusion that it does not need 'modeswitch' to make my three modems work, they work directly from the kernel, giving even more weight to the kernel regression theory as now the .26, .27 and .28 kernels (that I have access to) all work, but everything later requires usb-modeswitch to make one or more modem function.

EDIT2. A further conclusion which may be of interest is that I have yet to have any kernel fail to work with the Huawei K3565. So if you are lucky enough to have a choice (and wise enough to read this post first!) then you know which modem to ask for. It is the newest modem I have so maybe that makes a difference perhaps it works slightly differently. Someone did once suggest that the key to the variability of success with these devices could be down to firmware versions and perhaps this lends some credence to this argument, the newer the firmware the more likely the modem is to work??

[Husse]

+1
This also makes my work very hard - I don't have a single broadband dongle and when I installed my Sony Ericsson W700i gprs phone as a modem it just worked, albeit slow
I have seen reports of both fail and success in Helena in this respect I think

[pdc_2]

hi viking777; thanks for your thoughtful and detailed comments; it is a fast changing and unsteady area;

I have taken an interest in these modems; we now have a Huawei 160 and 220; and a Vodafone K3565-Z and a ZTE MF636;
I still find the 220 the easiest to configure up;
I followed the Ubuntu forum over the last couple of months, and many distressed folks had gone ahead and changed from 9.04 to 9.10 to find their mobile broadband no longer worked;

even the team at Betavine; who do the VMC (Vodafone MObile Connect) software, have expressed their dismay

http://www.betavine.net/bvportal/blog/v ... 1585066602

I am intrigued at subtle differences between the latest distros: The Vodafone K3565-Z will not run on mandriva2010; it will run on fedora12 and opensuse 11.2 (gnome on all three); and I get the ZTE MF636 to work with wvdial;

I agreed with the sentiments of the betavine team; (that you articulate); that the world will move more towards mobile broadband, and great for linux users if it is as simple as possible!

I guess the two packages that one can explore instead of using network manager are:

VMC from betavine and

umtsmon

VMC is not network specific I understand but should run any GSM system

[viking777]

That's a very interesting link there pdc_2, thanks for that. If nothing else it confirms the fact that I am not the only one that can't understand WIHIH !!

I used to use VMC a couple of years ago, back then it was just about the only way I could use my modem (I only had the E220 then), but I haven't used it for a while and it seems from what they say there isn't much point at the moment. I also used umtsmon quite a bit last summer and had reasonable, though not universal, success with it. Unfortunately I read recently that development on that project has more or less halted at the moment (I am not sure how true that is, I only heard it second hand) so it doesn't look like a good long term prospect.

Still the software that provides the most success for me is usb_modeswitch, although again it is not a 100% success rate and it only supports certain modems (luckily the ones I own are supported).

What intrigues me is the fact that in older kernels (like pclos and Suse 11.1) I get all three to work without additional software whereas in modern kernels this doesn't happen eg the last one I tested Suse 11.2. I am convinced there is something in this although I would not claim to know what it is.

I would have thought that with such innovative people as the producers of 'modeswitch', 'umtsmon' and 'VMC' all working on it as well as the kernel developers, this problem should have been solved long ago especially since, in my experience, around the 2.6.26/27 kernel they had it working anyhow.

[Husse]

Yes it's sad that newer kernels have problems older ones did not have
Cooperation and focus on the right thing is lacking everywhere - I see that in my work and other places all the time....

[imol]

Odd, my Huawei E220 and E182E both work without any problems under Both Mint 8 (and UBuntu 9.10) without any fiddling.

IMoL

[viking777]

Odd, my Huawei E220 and E182E both work without any problems under Both Mint 8 (and UBuntu 9.10) without any fiddling.

IMoL

Bizarre???

The whole thing gets stranger and stranger.

[Husse]

Hmm - what did Einstein say - God does not play dice
Seems like it when you look at this
Sorry I can't be of more help

[viking777]

Here is another little update to my original post in this thread.

Crunchbang Lite - kernel 2.6.26-13 - usb-modewsitch not required - All 3 modems work.

Notice the similarity to other entries? - 2.6.26 kernel and it works. Anything newer than 2.6.27 and it doesn't work (at least not fully and usually not without usb_modeswitch). This is not the same for everyone I know, but seems pretty consistent on my computer. I would love to know what changed after the .27 kernel that caused this. Of course it could just be a series of coincidences, but that is looking less and less likely to me.

BTW if you have a low spec computer that doesn't work with anything else (I do!) give Crunchbang Lite a try - it's a little belter

[roseanna]

Whats the difference between broadband and 56k modem? I'm buying a laptop but I need a fast internet for job communication. I know broadband is supposed to be fast, but is a 56k modem fast too? I have a 56k modem in this pc I use at home on dial up, but I when I connect it says 19.2kbps, it never gets higher. If a laptop comes with a 56k modem does that mean It will be double time than dial up at home?
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[viking777]

Whats the difference between broadband and 56k modem? I'm buying a laptop but I need a fast internet for job communication. I know broadband is supposed to be fast, but is a 56k modem fast too? I have a 56k modem in this pc I use at home on dial up, but I when I connect it says 19.2kbps, it never gets higher. If a laptop comes with a 56k modem does that mean It will be double time than dial up at home?

No roseanna, a 56k modem is not fast it is the same as you have at home and it doesn't work unless you have telephone line to plug it into. If you need a fast internet connection on the move then you need one of two things, wireless interenet (all modern laptops have this but you have to be within range of a wireless signal - usually found in libraries, cafes, hotels etc, but can work out quite expensive) or you need mobile broadband which is not without its problems either as I am sure you have read here. This can be either a contract or payg like a mobile phone. You can even use a mobile phone as a modem if you have the right phone.
Here is an example of one such deal in the UK. There are many different deals and providers, this is just one.

http://online.vodafone.co.uk/dispatch/P ... svl=value2

[paulh]

"sudo rmmod usb-storage && modprobe usbserial vendor=0x12d1 product=0x1003" gets my E220 working in Helena.

My question is: Is there a way to make this happen automatically at boot?

[viking777]

"sudo rmmod usb-storage && modprobe usbserial vendor=0x12d1 product=0x1003" gets my E220 working in Helena.

My question is: Is there a way to make this happen automatically at boot?

The trouble with that is it stops all usb storage devices from working, not just the modem.

[Husse]

paulh
If you don't care about the loss of USB storage add the command without the sudo to /etc/rc.local and it will be done at boot

[paulh]

Thanks guys, but no thanks. Will have to stay with the inconvenience for now - need USB.

[paulh]

What happened now? Suddenly the E220 won't connect; get a message: "ERROR: Module USB storage does not exist in /proc/modules"

Is this a kernel problem - anyone have a solution?

[viking777]

Code: Select all

sudo modprobe usb-storage 

Will replace it on a per session basis but there is no reason for it to have disappeared unless you adopted Husse's suggestion of two posts ago. There have been no kernel changes that I have seen to make this happen.

Check the command has worked with:

Code: Select all

lsmod|grep usb

Have a look in /lib/modules/2.6.31-16-generic/kernel/drivers/usb/storage and make sure you have the module 'usb-storage.ko' listed. (replace 2.6.31-16 with your kernel version if different).

I can't quite remember how you make the change permanent, I think you have to add it to /etc/modprobe.d but I am not sure - someone else will confirm that.

[paulh]

What happened?

Suddenly I can't connect my E220 - when I "sudo rmmod USB-storage && modprobe usbserial vendor=0x12d1 product=0x1003", I get message: "ERROR: Module USB storage does not exist in /proc/modules"

Is this a kernel issue?

Anyone got any ideas/solutions?

[paulh]

Sorry for the double post. Thought post didn't upload

[paulh]

Hi viking777

"sudo modprobe usb-storage" doesn't help.

'usb-storage.ko' exists in /lib/modules.../usb/storage (my kernel is 2.6.31-14).

I have no reference to 'usb-storage' in /etc/modprobe.d

This is wierd... was working perfectly (with 'sudo rmmod usb-storage && modprobe vendor=0x12d1 product=0x1003' after boot). No changes to system apart from regular software updates over past few days.

The modem does connect for +/- 20 seconds, then falls away. Works perfectly on XP so not a service provider issue.

Any thoughts on where else I might look?