7 ms·

How to run a city-wide wireless network from a drawer

207 points by adunk 5y ago

qprofyeh 5y ago
Off-topic: I find the 360-degree drone shot totally amazing. Is there a place where I can find more?
- ck2 5y ago
  It appears to be from a collection from this photographer: https://www.pexels.com/photo/aerial-view-of-city-during-night-time-9736019/ https://www.pexels.com/photo/aerial-view-of-city-during-nigh...
coinspin 5y ago
This sounds like one of those tools that was built internally that could spin out to be it's own project/startup. It's such a clever and easy way to solve their problems.
jotm 5y ago
Is this something you can get paid for, as in a job?
ja27 5y ago
> In the field, devices are far away from each other. So they will only be able to hear the devices that are next to it. And I'm out. Mesh networkers really should spend a bit of time re-learning all the lessons from decades of ham radio packet networks.
- anony23 5y ago
  Do you have any suggested content for someone who is starting from 0?
- schrectacular 5y ago
  I'm not a HAM guy - would you care to distill the lesson that they are ignoring? I infer that, by definition, this is not a mesh, but more of a train. And I further infer that a single node falling out would break the chain and split the "mesh". But I'm just guessing.
  - emteycz 5y ago
    What stops a node from redirecting traffic to another nearby node in case of failure/timeout?
    - schrectacular 5y ago
      OP's quoted text.
      - monocasa 5y ago
        It doesn't say how many nodes could hear each node in the emulated env, only that's it's a subset of the total, unlike the unemulated env where they're all in a drawer. There's nothing there that precludes having enough for nodes to route around failures as I see.
- myself248 5y ago
  I think both the statement and the criticism are oversimplifications. It sounds like the criticism hints at the hidden node problem. (Briefly: One of the largest problems in wireless networking. A and B can hear each other, B and C can hear each other, but A and C can't. So when C wants to talk to B, how does it know if A is already transmitting and B's receiver is already listening? In large networks this gets hugely important.) But it sounds like the simulation is already maximally pessimistic about it -- there's no RF attenuation in the drawer, so all the devices occupy the radio channel whenever they're transmitting. So I would imagine that software that works well in this case, would probably also do decently in the real world. (As opposed to software tested on a naively-simplified network of RF cabling and attenuators, which would not model the hidden node problem's complexities very well.) So, while the real world will surely be more complex than they hint at in their sentence, I think the simulation drawer is also better than you hint at in yours. There are nuances, of course, and frankly there are RF network simulators they could be using, but I think the presented MAC-filter approach is not terrible.
  - adunk 5y ago
    OP of the article here. You are absolutely correct. The statement in the article is very much a simplification: in the real world, wireless communication is tricky. Not only are there issues such as the hidden node problem (and the exposed node problem, for that matter), but it also changes over time. It is possible to take these issues into consideration, but as you say, that requires a very different infrastructure than what this article is talking about. The way we do it at Thingsquare is to use a software-based simulator where we can both emulate the software on the devices and have full control of the simulated radio medium - if we need it. Sometimes using RF attenuators and/or cabling is useful. In the end, what it comes down to that each tool has one or more use cases where it shines, but there is no one tool that fits all.
delabay 5y ago
What's OPs view of helium network? It basically solved the issue of network deployment for LoRaWAN. It covers the vast majority of American population centers, Western Europe, and soon south america and APAC.
- merlinscholz 5y ago
  Do you have a link for that? I can only find Blockchain stuff under that name
  - extra88 5y ago
    I think that's what they're referring to, www.helium.com. "Mining HNT with Hotspots is done via radio technology, not expensive or wasteful GPUs. … Hotspots work together to form a new global wireless network and undertake ‘Proof-of-Coverage’." "Tokens & Data Credits: The network uses two units of exchange: HNT, a new cryptocurrency, and Data Credits. Proof-of-Coverage: Our novel proof-of-work algorithm enables Hotspots to be rewarded trustlessly. Helium LongFi: LongFi combines the low-power, long-range LoRaWAN wireless protocol with the Helium Blockchain." I get the impression is it's to create a cryptocurrency motivation for providing good network coverage. I don't get how it works but assume, like all things involving blockchain, there are externalities or unintended effects that make it not a good solution.
    - delabay 5y ago
      Yes, it's an economic mechanism to build wireless networks. There are definitely externalities as you say. However what I find amazing is they successful built the network when all other traditional means of doing so had failed. See the recent bankruptcy of sigfox. Helium is the quintessential example of Blockchain doing obvious social good when all traditional means of accomplishing the same goal had failed.
      - detaro 5y ago
        I wouldn't call TheThingsNetwork "failed", and it's the same: open LoraWAN network, except without blockchain incentives.
jimmaswell 5y ago
Someone somewhere must have their device connected to the internet right? Is this just to benefit the one in a thousand with no wifi?
- detaro 5y ago
  What gave you the impression this is for end-user internet access?
  - jimmaswell 5y ago
    The page really isn't clear but I assumed it was for IoT devices like a coffee maker. If all the coffee makers talk to each other, great, but someone has to connect to the internet at some point. I'm clearly missing some context here.
xyst 5y ago
MAC address filtering comes with its own downsides. For one, it’s very easy to spoof. So you can act as a node in the mesh network if you copy the MAC address of a known node. Implications: elevated access within mesh network, capturing traffic between clients and the mesh network, localized disruption of mesh network due to unstable connection caused by duplicate MAC addresses on a single network
- tenacious_tuna 5y ago
  It doesn't sound like they're using MAC filtering for Real Security (TM), just to emulate device visibility in the lab.
- detaro 5y ago
  All that is entirely irrelevant for what they are describing in the post.
zackmorris 5y ago
I did a quick search to see if mesh networks have gone mainstream yet: https://futureprepping.com/mobile-phone-mesh-networks/ https://futureprepping.com/mobile-phone-mesh-networks/ The radio dongles are superfluous and I can't think of any engineering reason why all cell phones can't just communicate with others nearby already. Maybe not for cellular voice and data, but certainly for something akin to AppleTalk back in the 80s: https://en.wikipedia.org/wiki/AppleTalk https://en.wikipedia.org/wiki/AppleTalk When I got to college in 1995, all of the Macs were on the campus-wide LAN and lots of Mac users had their public folders shared. There were tons of apps and games and even little personal BBS-style areas where people posted stories and you could share files to their drop box. It was all free and open and frictionless and stands out vividly in my mind as a vision of what we thought the internet was going to be. If we had that, it would be trivial to run something like IPFS to bypass the ISPs, even without paid cellular service. Then anyone could connect through their tunnel provider of choice and bypass any privacy concerns. The speed would be proportional to the number of nodes, so many thousands of times faster than internet today is, or ever can be. With the debates around net neutrality and the cost of streaming, it's like we've forgotten that the only cost of the internet could be the electricity required to run a cell phone.
- dopidopHN 5y ago
  My bet is on LoRa being shipped with flagship phones.
  - Vladimof 5y ago
    An open alternative to LoRa would be nice... https://revspace.nl/DecodingLora https://revspace.nl/DecodingLora
- thrashh 5y ago
  The electricity required is precisely the problem why we don’t do it. And it’s not so much the power that it requires but that the extremely low energy density of lithium batteries means we have to minimize power usage as much as possible.
Uptrenda 5y ago
Wow, what a cool service. It would be fascinating to see what could be done if you bought a lot of plugin devices and then just gave them out to neighbors.
kragen 5y ago
Note that Adam Dunkels, who wrote this writeup and posted it here, is one of the most accomplished embedded programmers in the world; if you've done TCP/IP on a computer without an OS in the last ten years, you probably used his lwIP stack. What you might not know is that lwIP was originally written for his free-software operating system Contiki, which can run working web browsers not only on a Commodore 64 but even a Commodore PET. A city-sized IPv6 mesh network built out of handheld-sized devices was science fiction 25 years ago. Metricom's Ricochet showed it was possible, without the IPv6, about 23 years ago. And after decades of resistance and sandbagging from regulators, Thingsquare is finally making it happen in real life.

207 points by adunk 5y ago

qprofyeh 5y ago

Off-topic: I find the 360-degree drone shot totally amazing. Is there a place where I can find more?

ck2 5y ago
It appears to be from a collection from this photographer: https://www.pexels.com/photo/aerial-view-of-city-during-night-time-9736019/ https://www.pexels.com/photo/aerial-view-of-city-during-nigh...

coinspin 5y ago

This sounds like one of those tools that was built internally that could spin out to be it's own project/startup. It's such a clever and easy way to solve their problems.

jotm 5y ago

Is this something you can get paid for, as in a job?

ja27 5y ago

> In the field, devices are far away from each other. So they will only be able to hear the devices that are next to it. And I'm out. Mesh networkers really should spend a bit of time re-learning all the lessons from decades of ham radio packet networks.

anony23 5y ago
Do you have any suggested content for someone who is starting from 0?
schrectacular 5y ago
I'm not a HAM guy - would you care to distill the lesson that they are ignoring? I infer that, by definition, this is not a mesh, but more of a train. And I further infer that a single node falling out would break the chain and split the "mesh". But I'm just guessing.
- emteycz 5y ago
  What stops a node from redirecting traffic to another nearby node in case of failure/timeout?
  - schrectacular 5y ago
    OP's quoted text.
    - monocasa 5y ago
      It doesn't say how many nodes could hear each node in the emulated env, only that's it's a subset of the total, unlike the unemulated env where they're all in a drawer. There's nothing there that precludes having enough for nodes to route around failures as I see.
myself248 5y ago
I think both the statement and the criticism are oversimplifications. It sounds like the criticism hints at the hidden node problem. (Briefly: One of the largest problems in wireless networking. A and B can hear each other, B and C can hear each other, but A and C can't. So when C wants to talk to B, how does it know if A is already transmitting and B's receiver is already listening? In large networks this gets hugely important.) But it sounds like the simulation is already maximally pessimistic about it -- there's no RF attenuation in the drawer, so all the devices occupy the radio channel whenever they're transmitting. So I would imagine that software that works well in this case, would probably also do decently in the real world. (As opposed to software tested on a naively-simplified network of RF cabling and attenuators, which would not model the hidden node problem's complexities very well.) So, while the real world will surely be more complex than they hint at in their sentence, I think the simulation drawer is also better than you hint at in yours. There are nuances, of course, and frankly there are RF network simulators they could be using, but I think the presented MAC-filter approach is not terrible.
- adunk 5y ago
  OP of the article here. You are absolutely correct. The statement in the article is very much a simplification: in the real world, wireless communication is tricky. Not only are there issues such as the hidden node problem (and the exposed node problem, for that matter), but it also changes over time. It is possible to take these issues into consideration, but as you say, that requires a very different infrastructure than what this article is talking about. The way we do it at Thingsquare is to use a software-based simulator where we can both emulate the software on the devices and have full control of the simulated radio medium - if we need it. Sometimes using RF attenuators and/or cabling is useful. In the end, what it comes down to that each tool has one or more use cases where it shines, but there is no one tool that fits all.

delabay 5y ago

What's OPs view of helium network? It basically solved the issue of network deployment for LoRaWAN. It covers the vast majority of American population centers, Western Europe, and soon south america and APAC.

merlinscholz 5y ago
Do you have a link for that? I can only find Blockchain stuff under that name
- extra88 5y ago
  I think that's what they're referring to, www.helium.com. "Mining HNT with Hotspots is done via radio technology, not expensive or wasteful GPUs. … Hotspots work together to form a new global wireless network and undertake ‘Proof-of-Coverage’." "Tokens & Data Credits: The network uses two units of exchange: HNT, a new cryptocurrency, and Data Credits. Proof-of-Coverage: Our novel proof-of-work algorithm enables Hotspots to be rewarded trustlessly. Helium LongFi: LongFi combines the low-power, long-range LoRaWAN wireless protocol with the Helium Blockchain." I get the impression is it's to create a cryptocurrency motivation for providing good network coverage. I don't get how it works but assume, like all things involving blockchain, there are externalities or unintended effects that make it not a good solution.
  - delabay 5y ago
    Yes, it's an economic mechanism to build wireless networks. There are definitely externalities as you say. However what I find amazing is they successful built the network when all other traditional means of doing so had failed. See the recent bankruptcy of sigfox. Helium is the quintessential example of Blockchain doing obvious social good when all traditional means of accomplishing the same goal had failed.
    - detaro 5y ago
      I wouldn't call TheThingsNetwork "failed", and it's the same: open LoraWAN network, except without blockchain incentives.

jimmaswell 5y ago

Someone somewhere must have their device connected to the internet right? Is this just to benefit the one in a thousand with no wifi?

detaro 5y ago
What gave you the impression this is for end-user internet access?
- jimmaswell 5y ago
  The page really isn't clear but I assumed it was for IoT devices like a coffee maker. If all the coffee makers talk to each other, great, but someone has to connect to the internet at some point. I'm clearly missing some context here.

xyst 5y ago

MAC address filtering comes with its own downsides. For one, it’s very easy to spoof. So you can act as a node in the mesh network if you copy the MAC address of a known node. Implications: elevated access within mesh network, capturing traffic between clients and the mesh network, localized disruption of mesh network due to unstable connection caused by duplicate MAC addresses on a single network

tenacious_tuna 5y ago
It doesn't sound like they're using MAC filtering for Real Security (TM), just to emulate device visibility in the lab.
detaro 5y ago
All that is entirely irrelevant for what they are describing in the post.

zackmorris 5y ago

I did a quick search to see if mesh networks have gone mainstream yet: https://futureprepping.com/mobile-phone-mesh-networks/ https://futureprepping.com/mobile-phone-mesh-networks/ The radio dongles are superfluous and I can't think of any engineering reason why all cell phones can't just communicate with others nearby already. Maybe not for cellular voice and data, but certainly for something akin to AppleTalk back in the 80s: https://en.wikipedia.org/wiki/AppleTalk https://en.wikipedia.org/wiki/AppleTalk When I got to college in 1995, all of the Macs were on the campus-wide LAN and lots of Mac users had their public folders shared. There were tons of apps and games and even little personal BBS-style areas where people posted stories and you could share files to their drop box. It was all free and open and frictionless and stands out vividly in my mind as a vision of what we thought the internet was going to be. If we had that, it would be trivial to run something like IPFS to bypass the ISPs, even without paid cellular service. Then anyone could connect through their tunnel provider of choice and bypass any privacy concerns. The speed would be proportional to the number of nodes, so many thousands of times faster than internet today is, or ever can be. With the debates around net neutrality and the cost of streaming, it's like we've forgotten that the only cost of the internet could be the electricity required to run a cell phone.

dopidopHN 5y ago
My bet is on LoRa being shipped with flagship phones.
- Vladimof 5y ago
  An open alternative to LoRa would be nice... https://revspace.nl/DecodingLora https://revspace.nl/DecodingLora
thrashh 5y ago
The electricity required is precisely the problem why we don’t do it. And it’s not so much the power that it requires but that the extremely low energy density of lithium batteries means we have to minimize power usage as much as possible.

Uptrenda 5y ago

Wow, what a cool service. It would be fascinating to see what could be done if you bought a lot of plugin devices and then just gave them out to neighbors.

kragen 5y ago

Note that Adam Dunkels, who wrote this writeup and posted it here, is one of the most accomplished embedded programmers in the world; if you've done TCP/IP on a computer without an OS in the last ten years, you probably used his lwIP stack. What you might not know is that lwIP was originally written for his free-software operating system Contiki, which can run working web browsers not only on a Commodore 64 but even a Commodore PET. A city-sized IPv6 mesh network built out of handheld-sized devices was science fiction 25 years ago. Metricom's Ricochet showed it was possible, without the IPv6, about 23 years ago. And after decades of resistance and sandbagging from regulators, Thingsquare is finally making it happen in real life.