That’s not right. The round trip (which is what he’s measuring) is up-down-up-down which is 140,000 km. That’s half a second.

The Edgerouter 4 will definitely do a full 1 Gbps between two ports with NAT on. The ER4 (unlike some other Edgerouters) has also been rock-solid reliable for me; I have two that have been in use for I think 7 years without a failure. Of course that “7 years” is also kind of an issue because they are a 7 year old design that is still near the top of that line, and I understand there is unlikely to ever be a new Edgerouter model. If your Internet connection ever exceeds 1 Gbps there is no replacement that can use that (well, there’s the Edgerouter Infinity but that’s silly) but if that’s not an issue for you the ER4 is really very good.

So the ER4 will deliver 1 Gbps to or from anything ultimately attached to your switch that chooses to send or receive that fast, which is.about all a wired router can do for you. This is in fact why I like wired routers and the way you’ve built your network; not ever issue points at the same piece of equipment.

On my Android phone the exclamation point usually means there’s something wrong not with the WiFi but with the service it gets when connected to the WiFi, e.g. no working DHCP server or no working DNS server or no Internet connectivity. And if that is the issue then the “signal loss” you see may not be a problem with the router’s WiFi signal but instead might be the phone choosing to leave that network and look for another that provides working Internet service, reconnecting to try again when it finds no alternative.

To eliminate the WiFi as the issue try connecting something to an Ethernet port instead. If that fails to get Internet service and you fix what is causing that failure you’ll likely find the WiFi is fixed as well.

You don’t mention what kind of cable it is. If it is solid conductor 24 AWG cable it might be worth repairing, but if it is a premade patch cable with smaller stranded conductors (as is typical for that) just chuck it and buy a new one. Most of the connectors and punch-downs you can buy won’t work well with that and finding ones that do may cost you more in time and frustration than a replacement cable does.

I had two 3-day power outages at my house last winter, and the neighborhood up the hill from me (including my backyard neighbor) had another 2-day outage (it was rainy in California). I also have Tesla batteries and solar panels, which will generally keep my computer equipment and refrigerator running if I leave almost everything else off. And, to top that off, for hysterical reasons I also have both AT&T fiber and Xfinity Internet service.

For all 3 outages the Xfinity service went down not too long after the power failed and stayed that way until it came back on, while the AT&T service stayed up the entire time. YMMV though.