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Is there a DIY solution that can do this? With all features in DD-WRT or OpenWRT, I would have thought the community would have already solved this problem for cheap.

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A long time ago, I set up a mesh with a bunch of WRT-54Gs and OpenWRT using olsrd for the routing protocol. It worked pretty well as far as I could tell, but I never setup a proper test to see if multi-hop routing was working well. (My setup was within a house, so basically all the nodes were in range of each other.)

For any large mesh, using a proper routing protocol is a good idea; the default behavior of ethernet it to construct a spanning tree and prune any links that would result in a cycle, which leads to suboptimal routing if you have more than two routers.

There's been a lot of interesting research in wireless routing. One of the more interesting ideas [1] is to use the probability of packet loss as part of the link cost metric, to discourage routers from always using the path with the fewest number of hops, which might be very unreliable.

It's been about a decade since I looked at any of this stuff, so I don't know what the state of the art is these days.

[1] https://pdos.csail.mit.edu/papers/grid:mobicom03/paper.pdf

We're working on it at Meta Mesh Wireless Communities, a non-profit company putting together a mesh network in Pittsburgh as an educational and equipment-producing effort. Our AP150 is getting some attention and has been a cool platform for us to ship our mesh configuration.

http://www.metamesh.org <- the org http://www.metamesh.tech <- the tech & store http://www.pittmesh.net <- the network

The IETF Home Networking working group [0] has been working on the software side of this, standardizing things like HNCP [1] to allow for automatic configuration of a home network with multiple IPv6 routers. The Cerowrt [2] router firmware project included mesh networking using AHCP [3] and those packages made it upstream to OpenWRT. So there are quite a few ways to do this, and at least some of them have been pretty thoroughly tested in the wild.

[0] https://tools.ietf.org/wg/homenet/

[1] https://tools.ietf.org/html/rfc7788

[2] https://www.bufferbloat.net/projects/cerowrt/wiki/

[3] https://www.irif.fr/~jch/software/ahcp/

The "DIY" solution is mentioned in the article. Buy a bunch of standard WAPs (the Ubiquiti UniFi range is popular) and wire them together with ethernet.

The Ubiquiti APs (e.g., the AC-PRO) can uplink to each other wirelessly, but only through one hop.

Also, you're giving up half your antenna-seconds for that. I tried it and was not happy—the hardwired performance is generally great, though.

If you 1) don't have ethernet throughout the house, 2) don't have satellite internet, and 3) can spend a little more, I recommend a pair or more of MoCA adapters as backhaul for the APs. You'll likely get better performance than mesh networking.

Depends on how cheap you want to be. Use ethernet and disable all but one of the dhcp servers plugging the leaves LAN port to LAN port. Or just buy repeaters. I tend to have had bad experiences with cheap wifi routers with or without third party firmware.

DD-WRT/tomato/others do have mesh features but it depends on the radio chipset and other things.

You can just buy a 802.11ac repeater for $40.

I've tried doing this before and my devices "stick" to farther away access points as I walk across the house. Are there ways to solve this problem, and/or do the solutions mentioned in the article solve this problem?

No and probably not. The biggest issue with wifi is almost always the station/client. Clever units may send de-auth packets to try to get you to renegotiate with an AP with a stronger signal but nothing is guaranteed and some client stacks can be stubborn

The higher-end APs (like the aformentioned UniFi) do have a transparent roaming feature, where every AP broadcasts the same MAC, and the APs handle traffic handoff. No idea how well it works.

If you want a layer 2 mesh (like a switch over Wifi) use batman-adv and 802.11s - This works fine even on a 10$ TP-Link 841N. You likely want to have a model with 8mb flash and 64mb memory - otherwise there is not much stuff for other packages.

Use OpenWRT Chaos Calmer, that is the latest stable released and quite good documented at openwrt.org wiki.

This is something that should work fine: https://wiki.openwrt.org/doc/howto/mesh.batman

There was a split and now most of the former OpenWRT devs build LEDE - but they don't have a release yet, however if you need support for newer routers or it's there. It's pretty close to the Linux kernel and most fixes (and also breakage) are timely there. http://www.lede-project.org

for routing: There is olsrdv1 and the new and shiny OLSRv2 that uses IPv6 link-local addresses and has a new metric for optimizing links that takes a lot of stuff into account like packet loss, throughput and so on. https://olsrd.org

There is also babel where lot's of stuff is happening - there is experimental layer3 roaming https://github.com/jech/babeld https://github.com/tcatm/l3roamd

I'm not sure if that's true but I think batman is the best solution for smaller meshes (<50?) in bigger meshes layer2 overhead is a problem.

There are a lot of active communities related to mesh networking:

There is a yearly conference where they benchmark their mesh implementations against each other. Pretty interesting stuff: http://battlemesh.org/

It's really plug'n'play yet if you do it on your own and don't use a mesh firmware i.e. https://libre-mesh.org

https://internetfreedomfestival.org/wiki/index.php/Deploy_an...

Or the software used in a lot of places for freifunk.net meshes in Germany: https://github.com/freifunk-gluon

I'm sure I've forgotten something but these are projects that care about meshes.

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