I want to design an IoT device with cellular connectivity. It requires ~50MB upload per day at most, but with live high-frequency monitoring. I think a HSPA network will suffice. I would like for it to also be cheap (Less than $100 with global penta-band frequency support).

I noticed that there are end-device certified (PTCRB and GCF) embedded 'modems' available from companies like Nimbelink. However, they are expensive.

Now, I know about the existence of cheaper options like those from Ublox, for instance, which are 'modules', and not 'modems'. But Ublox's Lisa-U200, for instance is on GCF's list of certified modules.

It seems like that doesn't qualify and end-device certified, and I don't have the funds to certify it. But is it necessary? I wish to make this open source design, and say at best there will be a 100 of the devices with Ublox Lisa-U200 on the same operator. Will a network operator block these devices? How will they know it's all the same device, when clearly, there are development boards such as ARM mbed's C027 with the same chip set, and not on GCF database?

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    Welcome to the site. To clarify you're asking if a certified module might get your device blocked in comparison to using a complete certified modem, correct? – Helmar May 13 '17 at 10:48
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    @Helmar Yes, that's the gist of it, yes. – mehfoos yacoob May 13 '17 at 20:39
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    @Helmar: Note that when I say using the certified module, that's along with following their recommended specs other design aspects. – mehfoos yacoob May 13 '17 at 20:52
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    If I may ask, do these Ublox modules have valid IMIE numbers programmed? In many countries devices without valid IMEI numbers are blocked? – sob Jun 14 '17 at 5:57

If I understand the question correctly, you're proposing to ignore the legal requirements to avoid interfering with other radio users? Generally this is not enforced by the telecoms operator, it's enforced by the FCC, Ofcom or an equivalent. They may be able to compel the telecoms operator to identify you, and you potentially face criminal sanction, not just denial of service. The justification for this is that you may be interfering with other commercial or safety related radio operators.

However, I think you mis-understand the certification regime. Ublox (for example) certify their modules such that you can legally rely on their testing and avoid having to perform your own testing - so long as your use case comples with their specifications. This permits you to use the modules in the certified countries. It does not guarantee non-interference or that your device will not be banned, just that you will not have committed a criminal offence if there is a problem.

Using the u-blox dev board which you reference in a non-certified country would be just as illegal as using the module on a different board. Using the module with an inadequate power supply, or a non-conforming antenna is illegal.

Your concern should not be with the network operators - it is the radio spectrum enforcement authorities in each country (and potentially their customs/import controls).

Unless the individual operators impose specific usage conditions (along the lines of the no tethering condition which you might see with certain data packages), then there should be no difference between using a certified module or a certified end product - except for the other testing your end product may require for general EMC. Any operator specific conditions are liable to extend into your software stack rather than apply to the modem itself.

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    Thanks for the info. I do not wish to break the law, but wanted clarification on using certified modules without further PTCRB or GFC. If I use the ublox module described in countries where they have certified it, and I comply with their specification, but do not prove it through any official certification, can I get banned from a network? If so, how is my design different to the mbed C027 board from a network operator's persepctive? – mehfoos yacoob May 13 '17 at 20:50
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    My understanding is that if you use a module, as specified, you're fine (anywhere the module is certified). This is why modules are available, as well as bare ICs. Follow up with u-blox (its their business model to support you, they probably have documentation). – Sean Houlihane May 13 '17 at 22:18
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    Possibly dependant on region - I'm only familiar with the EU, and some of my experience is a little dated. – Sean Houlihane May 13 '17 at 22:20
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    If using a module as specified is fine, then is end device certification not necessary? Why is Nimbelink claiming they have "end device certification" and selling their product with a Telit chip set for more money? I would be very happy to just use the ublox module(following their specs) as it's way cheaper, but the crux of my question is to check if "end device certification" is necessary. – mehfoos yacoob May 13 '17 at 23:50
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    Marketing, and packaging a different product (the module needs to be built-in, and addresses a differnet market). A modem can (for example) be added to existing equipment, not designed in from scratch. – Sean Houlihane May 14 '17 at 9:48

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