Comment by Animats | Hacker News Reader

Comment by Animats | Hacker News Reader

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I had Ricochet. It was OK, but slow. It used little units bolted under street lights, with a little spiral antenna pointed down. It was abandoned in place some years later. You could still use it to talk to nearby locations, but the connection to the external Internet was gone.

It's certainly possible to build a 900MHz mesh network, but it can't deliver much bandwidth. Email and SMS, yes. Voice, only on slow days. Today's web, no way. It would be like building a network for Blackberries.

One of the more successful off-grid comm systems is SailMail.[1] This is worldwide email, over 10MHz, for boats. Down at 10MHz, radio can cross oceans. This was a side project of Stan Honey, who invented car navigation systems. He's seriously into sailing and holds records for crossing the Atlantic, sailing around the world, and such. So he developed this for the long-distance sail community. They maintain about 25 fixed stations around the world, and if you can connect to any of them over HF, you can send and receive email.

[1] https://sailmail.com/

Out of curiosity, do you know if some units are still around? The Wikipedia page isn't clear as to what happened to the existing hardware after the last acquirer's liquidation - was it just left in place, did the municipalities explicitly remove them or repurposed them for something else?

Some were around for years, but I haven't seen one in a while. I suppose they were removed as part of normal street-light maintenance. There may be some nodes, somewhere, still trying to connect.

This give me hope. I have been struggling with starting a small scale city wide mesh wifi... that shit is hard. I don’t need the bandwidth, just some connectivity. It’s pair really well with the bare bone internet that I would like to see back. ( HN being a fancy exemple of that )

Some are -- they pop up on local government auction sites (and even ebay) from time to time. The modems themselves are actually still quite useful, you can direct-dial between two of them using AT-style commands over the serial port, or they can be operated in a packet-radio style mode using tooling like strip: http://man.netbsd.org/NetBSD-6.0/strip.4

(STRIP was actually in the linux kernel, though I assume long gone or defunct -- the only things I still have talking via Ricochet are 2.4-era)

I have a couple of the lightpole radios (they listen for the modems on 900MHz and speak amongst themselves on 2.4GHz) and scored a single tower radio (talks to the lightpole radios and has an ethernet downlink) and have gotten them to speak with each other, but haven't had time to figure out the route mapping steps -- IIRC the deal is that the packet routing path information is stored upstream and delivered to the downstream radios. No idea if anyone ever decoded that format.

I messed around with this a lot in the immediate post-Ricochet era in between flashing silver WaveLAN cards to gold... fun times. It seems like it would be entirely possible now to run a simulated node using SDR.

Related: The Winlink system allows for off-grid email over the amateur "ham" radio service. It's available on most (all?) ham bands.

https://www.winlink.org/

> Voice, only on slow days

Then why did we have 900 MHz analog cordless phones in the 1990s?

It's not necessarily a limitation of bandwidth possible at 900MHz, it's a limitation of the normal equipment deployed and inefficiencies of mesh routing.

Those 900MHz analog phones were also usually low power, low distance, analog only devices with a few number of channels. Try having dozens of those phones all in the same room and see how useful they all are at once.

In that case, the spectrum was used as a replacement for the cable, in a 2 point system.

A mesh network is a completely different beast, with perhaps hundreds of thousands of nodes, spread around, and a good chuck of bandwidth being used for forwarding data between nodes.

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