I never said Wifi wasn't half-duplex. But that is not how half duplex connections work. They can only transmit in one direction at a time, but they can transmit in that one direction at full speed.
So if you have a 1Gbps half-duplex wired connection, you can still transfer a file from one computer to another at 1Gbps. However, if you start transferring in both directions at the same time, then both file transfers will happen at 0.5Gbps.
Wifi on the other hand is a completely different beast. Yes, it is half-duplex, but that's only part of what determines how fast you can transfer data.
When you connect with your smartphone to a Wireless network and it says it's connected at 867Mbps, that is just the rated maximum speed of the 802.11ac 2x2 connection. But in the background the wireless is doing lots of things to make sure you actually stay connected and don't drop a bunch of packets due to interference. The first thing it does is lower the actual connection speed.
Here is my laptop as an example:
View attachment 128067
This is on a 2x2 Wireless-AC card, and it's clearly getting faster than half of the rated speed. It isn't getting the full speed, because of interference. The wifi auto-negotiates in the background to lower speeds to give as stable of a connection as possible.
You aren't telling me anything I don't already know. I've used AT&T's FTTP. They offer great packages on their FTTP such as 6 Down / 1 Up, or 10 Down and 1.5 Up. Just because it's fiber doesn't mean it isn't still AT&T and they won't offer crap speeds and it doesn't mean it will be symmetrical either.
And, no Frontier isn't about cost. It's about their outdated DSL tech not being able to do anything better. Leaving Comcast to do and charge whatever they want. And even when there is some competition, in the areas with AT&T fiber, the packages are priced surprisingly similar and neither seems to ever bother to try to undercut the other. Kind of like gas stations...
Xfinity WiFi by Comcast offers internet on-the-go service at millions of hotspots. Find the fastest Xfinity WiFi hotspot near you!
www.xfinity.com
Yes, you should be getting unlimited data. They hide it, but on that page, towards the bottom, it says you get unlimited data. It looks like you aren't getting it, so I'd call them and sort it out to make sure your account was upgraded to the xFi modem rental.
If you had unlimited, it wouldn't mention anything about courtesy months, it would say something about unlimited data there instead.
Ok, whoever they sent out to install the service didn't know what they were doing then, or were lazy.
You should have a direct line run from the box on the outside of your home for each device. The Comcast installer will run these lines for you, and it should be free. So, for example, I've got 2 TVs and the cable modem. So I have 3 lines running from the outside box into my home. With the 1Gbps service, you can't have any splitters before the modem, it has to be directly connected to the outside box. Otherwise the signal is too weak, and the connection will drop out. You can get away with a splitter on the TV lines, but you definitely need a direct cable running to the modem.
Call them, complain, and tell them you want a line tech sent out to check the lines. A line tech will probably run a direct line to the modem.
If you've already got the cable, go for it. It will still do 1Gbps without a problem.