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Comment by mrb | Hacker News Reader

The system-on-chip is the MGM210L which needed to be powerful enough to run multiple wireless protocols (Zigbee, Thread, Bluetooth), so the lamp can be controlled by any of these. These are very complex protocols. The Thread spec for example is hundreds of pages. I did a formal security review of it on behalf of Google back in 2015. Bluetooth is even more complex. RF signal processing, packet structure, state machine, crypto, logical services, etc.

The software complexity of these protocols is greater than the complexity of a rudimentary 3D game like Doom, so it's expected that whatever chip can run these protocols can also run Doom.

Datasheet of MGM210L for the curious: https://www.silabs.com/documents/public/data-sheets/mgm210l-...

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>> The software complexity of these protocols is greater than the complexity of a rudimentary 3D game like Doom

That's unfortunate. Protocols, particularly those used for security should be a simple as possible. I know it's a hard problem and people tend to use what is available rather than solving the hard problem.

I would have thought they'd have specialized chip hardware already to deal with these, but maybe I don't know enough about that kinda thing. Pretty sure it'd have specialized hardware and/or instructions to deal with the cryptographic aspects though.

Baking something like that into hardware is probably not a good idea because then you can't update it when vulnerabilities are found.

Makes me smile to think that one day my bank account will be drained of all its BTC because I forgot to patch my bedside lamp last tuesday...

That would make me frown. Just saying.

But do you get software update (and deployment to your device) when vulnerabilities are found? ;)

The real reason is it reduces the cost (and duration) of iterating in the development phase.

Since Ikea update the firmware of the trådlös units quite often and has security updates in the changelog I would guess... yes They also mentions improvement of stability and performance towards different protocols in the changelogs.

My Hue lamps had their firmware updated through the app a couple of times, and I had them for 4-5 years.

It's already there.

The chip is SoC with Arm core, FP, Crypto Acceleration, DSP extensions and FPU unit plus radio parts.

complexity .. maybe, 80Mhz ... heck no. However, this is all off-the-shelf ware and as long as the energy consumption is not a problem, I am fine.

It's burst processing. You do actually need high processing speeds for short periods of time to implement network protocols like these effectively. Think cryptography, reliability, etc. The CPU isn't doing anything most of the time, but it makes a big difference if it can get the job done in 500μs instead of 5ms when there is something to do (like process a packet).

Also, higher clock speed = lower power consumption. It sounds counterintuitive, but getting the job done quickly so you can go back to low power mode sooner actually saves power, even if the instantaneous power draw while processing is higher.

Nearly all cryptography on MCUs is hardware based. It would have otherwise be completely impossible to do timing sensitive crypto work like WiFi, or BT.

The WiFi, or BT protocol stacks themselves are however almost always in software on MCUs simply because nobody would bother making a separate ASIC IP for that which will be outdated by the next standard errata.

Symmetric cryptography is often hardware based, but asymmetric crypto rarely is. The latter is commonly used for pairing/key exchanges, and would be painfully slow on a slow MCU.

> The Thread spec for example is hundreds of pages.

And this also assured it being dead on arrival.

Actually Thread is alive and kicking! It has a lot of momentum at the moment. But if it gets displaced, IMHO it's going to be by WiFi Ha-Low or successors.

It is not alive. I haven't seen a single device working with it, while I at least seen one Apple Home compatible device in an Apple store.

Tuya on other hand is just in every retail outlet, it's just people don't know that Tuya is under the bonnet.

Please stop lying to people: https://www.threadgroup.org/thread-group#OurMembers

I am not lying, the assortment of Thread based devices ever seeing sale is much smaller than the size of Thread's illustrious board of directors.

They literally have more talkshops per months than devices released.

That just means little more than "who bought or used the spec at some point." It has little bearing on contemporary real-world commercialization of the thread protocol.

Maybe not in your country(?) In the US there are quite a few commercial systems built on Thread: Apple HomePod mini, Google Nest security system, etc. Don't get me wrong: we are still very early in real-world deployments. It was just 2 years ago that the consortium/Google released the open source OpenThread which is when momentum really picked up.

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