On Sat, May 1, 2021 at 6:00 PM Eric House <[email protected]> wrote: > > Hi, > > I've signed up with Comcast down in Corvallis where they're the only game > in town. > > For now I'm renting their combo cable modem/wifi router. I'd rather spend > the $15/month on my own hardware, and I trust OpenWrt over their software. > > It seems you can't get cable modems whose firmware can be replaced. > Something about how a glitch in the cable protocols could take down a > neighborhood. :-) So I figure I'll get a dumb cable<-->ethernet box, plug > it in and forget it.
The first thing to understand is that, even if you own the cable modem, the cable company controls that device. When you plug it in, the first 15 minutes of "activating" it, is them downloading their version of the firmware and configuration. To me, this means that the cable modem is on their side of the wall. As a result, I don't want wifi on the cable modem, because that can act as a sensor in your local environment. I want the cable modem to be a dumb bridge media converter between coax and ethernet, and then use a gateway device of my own that they do not have any administrative control over to be the firewall on my local network. As a result, for the cable modem I want something they support, but with one coax and one ethernet port, like one of the SurfBoard modems, like: https://www.amazon.com/Motorola-SURFboard-SB6141-DOCSIS-High-Speed/dp/B007IMPMW4/ or faster, newer, more future-proof, and expensive, https://www.amazon.com/ARRIS-SURFboard-Approved-SB8200-Frustration/dp/B07DY16W2Z/ > > That leaves me choosing between one or two devices for the router and > access point parts. In the past I've used separate boxes, with OpenWRT on a > wired-only router and a cheap access point in its DMZ. I'd like to find a > single box that does both, but the ones "recommended" (inevitably with > "click to check price on Amazon" links) by industry sites are usually more > expensive than two boxes would be. There's cheaper dual-purpose hardware > that ought to suffice, but there are gotchas I don't understand, e.g. > whatever causes my Raspberry Pi 4 running as an access point to be 1/10 the > speed of the cable modem/access point it's plugged into. Raspberry Pi's don't make good routers or access points. If you can get away with one access point from a spatial coverage point of view, having them integrated in one device is reasonable. If you want to put the gateway near where the wire comes into the building, but need good wireless coverage somewhere else, then that argues for two devices, e.g., a wired network in the basement, but an access point in the main living space. If you are going the split route, the Ubiquiti ER-X is a reasonably priced ($60-ish) no-wifi gateway device that has good OpenWrt support, has gigabit ports and can route/NAT at reasonable fractions of that. Newer access points have been moving to ARM based CPUs and can both route fast and have fast 802.11ac radios, but they are spendier. And you have to be careful about OpenWrt support. You should avoid the Linksys stuff that's based on the Marvell radios, despite the hype about the homage to the old WRT routers and open source, the wifi drivers were thrown over a wall and abandoned by the vendor. Mediatek or Atheros radios are the way to go, and check for support of the exact device you are looking at. All of this kind of depends on your budget. An older Archer C7 v2 I have works fine, is available on ebay, has decent OpenWrt support. It might have trouble routing/NAT'ing at 450Mbps, but you should get some substantial fraction of that (I use mine as a dumb AP and I haven't noticed a speed constraint). You do want dual-band on anything you are buying. If you are going for super cheap, just make sure it has more than 32MB of RAM and more than 8MB of flash, or you won't reasonably be able to put modern OpenWrt on it. -- Russell Senior [email protected] _______________________________________________ PLUG: https://pdxlinux.org PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
