Remix

Sorry for the major delay, I finally found time to test this without disturbing too many people. Please note that my results aren't entirely scientific, and will likely vary especially in your usage. I'll explain why.
 
My findings were that 1080p 30fps video would play on a 3 Mbps connection in my scenario, though it barely hung on. I loaded a ~16 minute 1080p video over wireless, throttled to 3 Mbps at the router (not AP). The buffer-health stayed between 1 second and 2 seconds, so not much buffer room. Any small blip would likely cause buffering. Furthermore, the video took a few seconds to actually play. It's not quick, but when started it'll play. I'd allow it a bit of time by itself to buffer-ahead and compensate for any anomalies with the Internet connection itself. That being said, the two main factors it does come down to are:
Dedicated Internet: You have to be the only device actively using the Internet, I'm sure if another device was doing even Web-Browsing it wouldn't work very well. Buffer: Give it time to load and compensate for any anomalies, otherwise do expect it to randomly buffer. Now, the part that gets confusing. My guess is that it'd not work given your circumstances. If you're throttled to 3 Mbps, you'll have blufferbloat. Blufferboat is essentially your router sending too much data, and it getting "backed up". In my scenario, I couldn't mimic that because I was on a 250 Mbps connection, and throttling the router manually still left overhead. Speedtests peaked on the router at 2.96. If your ISP does any oversubscription, you do have a shot of video playing. For example, Comcast gives subscribers a 20% oversubscription to compensate for buffer and anomalies. That being said, when I throttled my connection to 3.6 Mbps 1080p video played much more fluent giving me an extra 3-5 seconds of buffer. This may work...

Sorry for the major delay, I finally found time to test this without disturbing too many people. Please note that my results aren't entirely scientific, and will likely vary especially in your usage. I'll explain why.
 
My findings were that 1080p 30fps video would play on a 3 Mbps connection in my scenario, though it barely hung on. I loaded a ~16 minute 1080p video over wireless, throttled to 3 Mbps at the router (not AP). The buffer-health stayed between 1 second and 2 seconds, so not much buffer room. Any small blip would likely cause buffering. Furthermore, the video took a few seconds to actually play. It's not quick, but when started it'll play. I'd allow it a bit of time by itself to buffer-ahead and compensate for any anomalies with the Internet connection itself. That being said, the two main factors it does come down to are:
Dedicated Internet: You have to be the only device actively using the Internet, I'm sure if another device was doing even Web-Browsing it wouldn't work very well. Buffer: Give it time to load and compensate for any anomalies, otherwise do expect it to randomly buffer. Now, the part that gets confusing. My guess is that it'd not work given your circumstances. If you're throttled to 3 Mbps, you'll have blufferbloat. Blufferboat is essentially your router sending too much data, and it getting "backed up". In my scenario, I couldn't mimic that because I was on a 250 Mbps connection, and throttling the router manually still left overhead. Speedtests peaked on the router at 2.96. If your ISP does any oversubscription, you do have a shot of video playing. For example, Comcast gives subscribers a 20% oversubscription to compensate for buffer and anomalies. That being said, when I throttled my connection to 3.6 Mbps 1080p video played much more fluent giving me an extra 3-5 seconds of buffer. This may work...

YouTube will prefetch content to compensate for irregularities in bandwidth essentially acting as cache. I know YouTube (480p) uses 1.5 Mbps, so generally speaking 720p will surely be more playable at 3 Mbps.
 
When I get home I'll test it out for you. I'll throttle my PC to 3 Mbps from the AP and let you know how it handles.

YouTube will prefetch content to compensate for irregularities in bandwidth essentially acting as cache. I know YouTube (480p) uses 1.5 Mbps, so generally speaking 720p will surely be more playable at 3 Mbps.
 
When I get home I'll test it out for you. I'll throttle my PC to 3 Mbps from the AP and let you know how it handles.

I'd have to agree unless they're fairly aggressive on the backend with Layer 7 inspection, any VPN that uses port 53, 80, or 443 should easily work on the network. I've built networks for high schools, and I know our policy is to close ports that are unnecessary and follow CIPA. While not necessary we take this a step further by blocking VPNs. This isn't really an issue in the district, but nowadays anyone can go out and purchase a VPN. This ensures our administrators and teachers that we've done our best to prevent students from accessing sensitive content.
 
 

This will renew his local IP, not external IP. And likely receive the same DHCP IP anyway...
This is inaccurate. Regardless of the strength of the DDoS attack, it'll cap out your modem at the profile assigned to the modem. If the node became saturated by a DDoS Attack, the subscriber would likely lose TV and Phone service too. The way they distribute bandwidth isn't to the "neighborhood". It's to the CMTS which may be fed by copper or fiber. Due to the recent deployments of Node+0, most CMTS' are being fed by fiber.
 
Finally... to answer OPs question:
You must change the MAC Address of the router, and reboot the modem (and possibly router too). Your router receives an IP via DHCP. To change the IP, you must wait for the lease to renew... (requiring you to shut down all equipment for a period of time) or forcefully change it by switching the MAC address. If you have an all-in-one unit, this would mean purchasing a new router and placing the unit in bridge mode or replacing the all-in-one unit overall. If you're in need of frequent changes, shop for a router (EdgeRouter series) that will let you manually change the MAC Address requiring a simple reboot to be back online.

I don't know how things work for DSL, where you have a dedicated line per residence to the telco, but for DOCSIS you have you have a limited amount of bandwidth that is shared for an entire neighborhood, or possibly part of a neighborhood (in the city it might be per block or for a few blocks). Depending on the amplifiers and splitters, you have between 750 and 1000MHz to play with. But before you can talk about internet use, you first have to allocate a large portion of that bandwidth to TV channels. Each analog TV channel (NTSC) uses 6 MHz. Right before the advent of digital TV (QAM), it was common to have 60-80 channels available on cable. That's 360-480MHz already in use out of 750-1000, meaning about 1/3 to 3/5 of the bandwidth. Digital TV improved this greatly, now we can put 4 SD channels, 2 720p channels, or 1 1080p channel in that 6MHz spacing - this is why you may see channels with a period or dash in the middle, like 6.2 which means the second channel on the 6th frequency band. Most cable companies still offer SD channels for a large portion because it allows them to offer greater internet speeds, or conversely more channels without taking up as much bandwidth.
 
Up to this point we are only discussing physical limitations. It is basically impossible to use more than 1000MHz on coax unless you want amplifiers every 50 feet.
 
From here we start to talk about ways the cable company might be screwing you a bit. Of the remaining 400-700MHz on the coax, this must be split up between all the houses in a given "cable plant". A cable plant is all the houses and businesses that share a single headend. Every single communication in a cable plant is broadcast - your modem actually receives every bit of data that the other modems upload, and also every bit of data someone else is downloading (the communications are encrypted between the modem and the headend). This, more than anything else, is why your internet speeds slow down in the early evening. At the time of installing the cable plant, you have to decide how big or small it will be. Say there is a new neighborhood of 1000 houses being built - how many seperate cable plants do you install? 10, each with 100 houses? 4, each with 250? The cable company has to decide now, at the time the coax is being laid, because separating it in the future is very costly - more costly than separating it now, but they don't want to spend a lot of money now either. This is the first place the cable company can screw you. If they think the neighborhood is going to be a less wealthy one, they will put more houses per network than average. If they think it will be a very wealthy neighborhood, they will put less houses than average per network.
 
Also at the time you install the cable plant, you have to decide how the available bandwidth (after subtracting TV service) is to be divided between uploads and downloads. If you devote too much bandwidth to uploads, it will go unused. Devote too little and you end up causing congestion. I don't have any data to back this up, but my own experience of working for an ISP is that normally, upload traffic is 10-15% of downloads - and this is even if the bandwidth caps are removed (sometimes our system is a bit inconsistent about applying the upload cap). At some point, the cable companies all settled on around 35MHz for uploads for residential, and more for areas where more business use is expected. The reason this has to be decided when you install the cable plant, is that the amount of upload traffic has to be set in the amplifiers. The amplifiers don't just have to amplify traffic downstream, towards the users, but also have to amplify the upload traffic upstream, back towards the headend. If you don't set this properly, you will royally screw up your signals. So once a cable plant is installed, you have to reconfigure or replace every amplifier in the entire area to increase upload speeds.
 
Beyond this first few years when cable systems were a new thing, you enter a chicken and egg situation. Why are uploads a fraction of downloads? Because that's how the amplifiers are configured. Why are the amplifiers configured that way? Because upload traffic is a fraction of download traffic. It can be argued that upload traffic would be higher if the upload speeds were symmetrical, but on a DOCSIS system you would never be able to test that theory. But I've see the aggregate usage of 500-5000 residents in apartment complexes, that share fiber connections between 500 and 10,000 Mb/s, and I can tell you that if the upload cap is removed, upload traffic barely increases, and sits around 10-15% - and this is on all-ethernet networks, where each resident can theoretically get gigabit in each direction.

Intel hands down. They've been in the business longer, and the chip simply works. Intel supports a wider variety of protocols, some of which I did mention previously. 

I dont think you read his post at all. You see, he is asking for an access point. He already has ethernet jacks. He doesnt need more.
 
Holy crap read his post. HE ALREADY HAS ETHERNET. HE NEEDS AN ACCESS POINT.
 
 
Anyway, like I said before, you are looking for an access point. It creates or expands a wifi network. Access points are different from routers in that they have no firewall, routing, or NAT. They pretty much just convert ethernet to wifi. I suggest you get the https://www.amazon.com/Ubiquiti-Unifi-Ap-AC-Lite-UAPACLITEUS/dp/B015PR20GY
 
It will allow you to extend your wifi network. Keep in mind that without 2 of the same access points, you will not be able to just extend your wifi signal. You will be creating a different network.

Fair point, I was just trying to quantify it rather than just saying one was better than the other. For this problem MoCA + WiFi is probably the most suitable option. But for the lurkers that's not necessarily their best option. Which option is the best will vary depending on what gear/cabling is already done, what the speed requirements are and what the budget is. 

The only way for DSL to competitive is for them to overhaul their networks and deploy G. Fast. It costs an ISP close to $24,000 for ~100 ports at the DSLAM. The cost to upgrade the infrastructure would be astronomical, which is why we don't see it happening. Deploying fiber in some cases is more profitable, which is probably the reason we see Fiber being deployed in some cases instead. DSL companies have neglected their copper networks, and it's coming back to bite them in the ass. DOCSIS 3.1 is a much cheaper alternative because it's essentially an upgrade to DOCSIS 3.0. I honestly couldn't tell you the last time I saw a tech working at the V. Rad (DSLAM). I see Comcast out periodically replacing and tuning amps, and doing "health checks" on hardware.
 
The end result is this. G. Fast claims gigabit speeds, but DOCSIS 3.1 is capable of 10 Gbps. The FCC defines broadband as 25 Mbps/3 Mbps, which many Americans don't have access too. I realize that other countries are lucky to receive those speeds. Guyana has a maximum speed of 10/10 for Businesses, which is crazy. [/rant]

Let's self-diagnose the issue with Comcast first. Can you post your modem/gateways signal levels and report if you're using Wireless or Wired when conducting the Speedtest?
 
Concerning DSL (At&t), I can tell you my personal experience with both. I had At&t for ~8 years before switching to Comcast, and the reason for switching was simply reliability. We'd have technicians out every 4-6 months because of equipment failures. The pings with At&t were higher, but I also lived on the edge of coverage for 24 Mbps and 18 Mbps. We had to manually request them to change the profile to enable us to purchase a 24 Mbps package. The differential in pings was about 10ms to gameservers you are from the node, the speeds decrease... and pings increase.
 
My recommendation for you would be to continue to use Comcast. Diagnose your problem here. Talk to Comcast after the problem has been resolved, and ask to renew your contract. This will tie you in for up to 2-3 years, but also can lower your bill. 

Worst option: Buying a new router. It won't make things worse but if your issue is coverage it probably won't make it better either
Not Much Better: WiFi Range extenders. Will they extend range? Well sure. But they'll also halve your bandwidth or worse....
Possibly ok: Mesh WiFi system. Some of these are just glorified range extenders but some have a dedicated radio for backhaul. A bit pricey but
Not Bad: Powerline + WiFi combo units. These use powerline for backhaul which adds another variable. But potentially greater speeds is the result
Best: Run Ethernet to where you want good WiFi and add access points. The only limitation here is the WiFi spec itself

This type of QoS isn't gonna work for SSL based applications, and to be honest... it doesn't work very well with Non-SSL applications either. Why are you setting up QoS, what are you trying to achieve?
 
Also, you're behind on Firmware... quite a bit.

Use another PC and transfer them with a USB drive?

Oh absolutely. The RF environment would be terrible. 
There isn't a science to it. There is no doubt that tells me the 940n will provide you with slightly more coverage... not very much, but it will provide you with faster speeds overall with the limitations of 2.4GHz. The 940n to me looks like a slightly upgraded version of the 740n. Reception Sensitivity just looks like you'll achieve faster speeds in the areas where you may have not before. They still have the same Transmit Power, so something tells me you won't see a huge range improvement. Probably not even 10%.

Oh absolutely. The RF environment would be terrible. 
There isn't a science to it. There is no doubt that tells me the 940n will provide you with slightly more coverage... not very much, but it will provide you with faster speeds overall with the limitations of 2.4GHz. The 940n to me looks like a slightly upgraded version of the 740n. Reception Sensitivity just looks like you'll achieve faster speeds in the areas where you may have not before. They still have the same Transmit Power, so something tells me you won't see a huge range improvement. Probably not even 10%.

Ubiquiti is a great brand, I cannot relate. Being you've gone the prosumer/small business route for Access Points, I'll assume you don't intend on spending much more than what you did with Ubiquiti. While I could recommend you get some Cisco Meraki product and pay some expensive rate, you could look into something like Mikrotik. I know Linksys makes a business grade AP that is affordable.
 
If you don't mind, run this command via SSH on your Ubiquiti APs. This fixed many problems in earlier firmware with Ubiquiti. Also make sure they're up to date, this last update did something... but it improved speeds overall and roaming is much quicker. 
 
Via SSH, users can apply syswrapper.sh restore-default. The UAP should quickly reboot with factory default settings. 
 
That will reset it to factory, but something about it speeds up the APs. Update the FW, and you shouldn't have an issue.

Having ports forwarded (open) won't help nor harm a DDoS Attack. If you run a service with a port open, and it is targetted for quantity and not bandwidth... it may overload the computer. Changing your IP depends on the ISP. Here in the United States, ISPs like Comcast give IPs via DHCP assigned to the MAC Address. If you change the routers MAC, the IP changes. At&t (DSL), Frontier FiOS, Verizon FiOS, etc... does it slightly different, as the devices they issue don't allow you to change the IP. Frontier Communications (in non-FIOS areas) will change your IP quite frequently, they'll change much quicker due to shorter DHCP leases.
 
It all depends. 

Having ports forwarded (open) won't help nor harm a DDoS Attack. If you run a service with a port open, and it is targetted for quantity and not bandwidth... it may overload the computer. Changing your IP depends on the ISP. Here in the United States, ISPs like Comcast give IPs via DHCP assigned to the MAC Address. If you change the routers MAC, the IP changes. At&t (DSL), Frontier FiOS, Verizon FiOS, etc... does it slightly different, as the devices they issue don't allow you to change the IP. Frontier Communications (in non-FIOS areas) will change your IP quite frequently, they'll change much quicker due to shorter DHCP leases.
 
It all depends. 

Converts the existing (or new) Coax in your home into Ethernet.

If you have coax availability, you could consider an MoCA adapter. That'd be almost ideal providing you with both speed and low latency. Unlike Powerline, MoCA is pretty solid.
 
In my experience, Powerline provided a higher ping, with less fluctuation. Wireless provides me with pings to the router from 1-10ms, while Powerline stayed between 4-6ms. Wireless provided superior speed though. As others have mentioned, this highly depends on the electrical wiring inside your home. Despite how new the home, it's honestly the luck of the draw when it comes to Powerline. If you live in the UK, they seem to have better experience with Powerline overall. My best recommendation is to purchase a top-of-the-line Powerline kit, and experiment with that.

If you have coax available in your home, please consider using MoCA adapters over Powerline. Powerline will probably never exceed 100 Mbps in your home, despite being marked as Gigabit. Many variables come into play with Powerline, because it uses the existing wiring in your home. It may seem like something you don't want to do, but you should consider running an ethernet cable if at all possible. If you cannot do that, consider MoCA as an alternative. MoCA will be much more stable, and provide higher speeds.

Sophos Home is absolutely free and works like a charm. I pair this with GlassWire, which allows me to see exactly what is happening on my computer, and see where my computer is connecting to outside my home (and inside) as well as which applications have changed versions. The solution isn't automatic, with the exception of Sophos... but I don't need obstacles in my way trying to use the internet. I'd rather have Sophos give me a warning, and let me proceed to the questionable website, than block it and make me manually whitelist it.
 
This isn't the solution for everyone, but it sure does give you superior control. 

Damn I have to sign into AT&T's website to disable an option in order to watch 4K video on a 5 inch screen? Oh the humanity!

For a lot of people, if not most they won't notice the drop in video quality but they probably will notice a drop in data usage that can now be spent elsewhere. I would only be angry if you had to pay to disable it.