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Comment by tomohawk | Hacker News Reader

Is there a reason they're using cell networks to communicate instead of just communicating over the power lines? These devices are meant to be in place for decades, so even a custom solution seems like it would be worth it.

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I worked on this, like 15 years ago, but ultimately after you go out of lab, there is so much garbage in the network that a lot of time this is not feasible.

Is there an existing mass-produced solution that can do it? The normal power line ethernet devices can handle ~300m and degrade quickly with noise. You'd need something much more specialised to go low speed high distance and able to handle lots of unsynchronized devices on the same line.

More common solutions installed in other places are dedicated mesh networks like Gridstream or AcuMesh. I'm really not sure why would the energy companies go for GSM instead. This is not just for the cities - Gridstream can reach a few km away.

On the other hand here's a buzzword-heavy ad from Thales that pushes for GSM https://www.thalesgroup.com/en/markets/digital-identity-and-...

Edit: apparently the powerline based data exists in the wild. (Keyword: PLC, but it's only one-way) Here's an interesting report from an Australian provider https://www.aemc.gov.au/sites/default/files/content/1494afbe... 10 years ago they were 46% rf mesh, 39% powerline data, 0.1% GSM. It's hard to find something more recent, but local mobile telcos had a lot of announcements / ads in later years, so the trend may have moved as well...

A decent global market overview from 2019 https://www.smart-energy.com/magazine-article/ami-penetratio...

You've gotten some answers below, but one answer is: There are several common ways of handling this, from powerline communication to cellular to LPWAN approaches, and all of them are in use, with different trade-offs. There's no one standard for smart metering infrastructure. Older AMR approaches often would just broadcast a signal that you could pick up with a vehicle driving around the neighborhood, but they're one way only. AMI uses cell, PLC, LPWAN, and sometimes zigbee (to a neighborhood gateway). What your meter uses depends on your power company and when it was installed.

That definitely exists, but AFAIK it requires special equipment to get the signal across transformers. Not much of a problem in urban environments, but e.g. in low-density areas in the US, where every house has its own transformer, it might be a problem.

signalling/communicating through the zero cross of the AC is trivial as long as there is a galvanic connection (wire). Once you get to transformers nothing much happens unless their is a module on the secondary to intercept it and then use other channels to ferry the data. In other words each transformer would need to have a communication device/router - I suppose that's way more expensive than ad-hoc modules per meter.

A custom solution would only be worth it if companies looked that far ahead instead of maximizing short-term profits.

Homes tend to have internet connections!

What if the home is unoccupied?

What if the user has a data cap?

What if the user has a misconfigured firewall?

Personally, with the exception of friends and family phones and tablets, I say "not my device, not my network, not my problem."

You just set it so that if there’s a communication issue, it defaults to some “high cost” mode.

People will plug it into the Internet to get their little discount.

Exactly if it’s not broadcast, periodically the old manual system kicks in and the financial incentives to encourage use makes sense.

And network security is another important aspect that can be a challenge but ultimately a benefit if better network security is needed and implemented standard with a clan for iot

If it were done intelligently (hint: it won't be) they'd be IoT devices designed to ONLY transmit outwards in some encoded method, so that the only risk patterns are leaking data and failing to send data.

Of course, in a intelligent world, the local power utility would be just that, local, and only involved in the last-mile connections of power and fiber, and let who actually sends down those be handled at the central "hubs".

Then since data and power were handled by the same company, your electric meter would just have a connection to your fiber router.

This would be too easy so it won't ever be done.

The meters tend not to have a user interface that would allow someone to configure them to connect to the home internet router.

Oh heck no. I have enough concerns about the security of those devices, I certainly don't want them hanging off the side of everyone's home network. I have enough expertise to put them on a separate network isolated from anything I care about, but the average punter doesn't.

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