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Comment by untangle | Hacker News Reader

I don't know who this analysis is aimed at but I would advise caution in trying to apply it.

My main criticisms of the article are that it: (1) ignores modern wi-fi mesh technology; (2) oversimplifies "solutions" to the point of false equivalencies; (3) ignores performance and convenience concerns; (4) uses vague language ("it works"); and (5) treats "wi-fi" as a black box that operates in a vacuum and is not amenable to tuning (channels, power levels, freq's, etc.).

Ironically, the author's "buddy wi-fi" proposal embodies a subset of the capabilities of a current consumer mesh setup such as the Amplifi product that I use in my 3-story home.

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> I don't know who this analysis is aimed at...

I can answer that - this is a slightly edited version of something Avery wrote internally when we were both working on wifi routers for Google Fiber. Imagine that you wanted to explain to someone why it's hard to build a good wifi extender/repeater (and therefore why you need additional headcount to do so).

What's true about modern meshes that obviates the conditional probability of success? This'll be news to me!

Modern meshes still often have a choke point. Kill enough nodes at the right point in the mesh and the reliability degrades quickly as the backhaul links get oversubscribed. At least that's what I think OP meant :)

Intriguingly, I think my Google OnHub devices use spanning tree to find Internet across the mesh. I actually wired up both rather than use mesh networks on their own, though, and a bug in my Cisco wired switch's use of spanning tree was what caused problems -- despite having the cables connected, and ethernet running just fine between them, the spanning tree figured transmitting over wireless from one OnHub to the other would be faster than the ethernet switch between them. (The fix was to disable broken, manual spanning tree settings on the Cisco switch.)

This indicates to me that if you had a dozen Google Wi-Fi devices and a few of them had ethernet connections, the rest would quickly find the shortest path from your device to the AP you're connected to the nearest mesh device with the fastest ethernet to the outside world. I'm not sure how the hops are weighted though, presumably reliability and signal strength plays a role.

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