Why does my WiFi seem slow and how can I improve it?
September 25, 2017 10:18 AM   Subscribe

Salient facts below, followed by questions: We have “up to 500 Mbps” downstream residential cable Internet. Alone in the house, on my brand new phone, Speedtest.net tells me I get 84 Mbps downstream. It’s behaving more slowly than I’d expect for being the only thing on the network. Plus, at a given time we could have any permutation of Roku, iPad micnis, smartphones and laptops connected. Two adults and two school age kids’ worth of screens.

But everything acts slow-to-load, on phones, tablets and laptops alike. Streaming TV usually seems ok but not great. Lots of hourglassing. Lots of YouTube Kids not loading.

Our house is mostly stud and plaster, 1920s era, about 1900 sqft between two floors. Cable enters the house on the ground floor, via a one-piece modem-router thing that we own.

Questions are:

1) Should I be expecting higher speeds?

2) If that’s a reasonable speed to the speed test server, what else could be going on here?

3) If it isn’t a reasonable speed, can I do anything other than try various different cable companies?

4) I’m willing to throw a little money at new modems, routers, extenders, or a monthly business type plan, but I need some nudges in the right direction. I’ve done some research about improving the network strength upstairs but if it’s overall lousy there’s no point.
posted by chesty_a_arthur to Computers & Internet (13 answers total) 6 users marked this as a favorite
Speedtest is generally reliable. I would trust the speed test that is done through a WIRED connection to get your true speeds. I'd also not trust a phone browser's interpretation of Speedtest.net.

500 megabit/sec is probably pretty high up there for most cable providers. One caveat: ISPs will advertise their speeds in megaBITS, but most internet stuff is expressed in megaBYTES/second. Divide megabit number by 8 to arrive at your megaBYTES/second. Also, be aware that ISPs generally give both speeds combined as their "speeds," so you may have 400 down/100 up, which is their intepretation of 500mbps speed

Do you know if your modem-router is broadcasting in 2.4GHz or 5.0GHz (or both)? 2.4GHz doesn't carry as much info, but is better at penetrance in a house. 5.0GHz carries more info, but falls short in range.
posted by kuanes at 10:25 AM on September 25, 2017 [5 favorites]

Speedtest is a reasonable test. I prefer DSL Reports' tool though. Be aware some ISPs cheat and give priority to speed tests, but it's still a useful tool.

The #1 thing you should do to diagnose this is to plug your laptop in via a cable to the router. WiFi causes all sorts of problems and you will never see anywhere near 500Mbps on it. If it works a lot better when plugged in, then you need to improve the WiFi in your house. That's a different topic but relatively easy if you throw money at it. (It's quite possible plugged in you will be limited to 100Mbps; if you see a solid 100Mbps that's not a bad sign really.)

Some other ideas:
  • One possible cause of slowness is the ISP's DNS server may suck. Try using Google DNS and see if it improves anything,
  • Cable modem speeds can vary by time of day and neighborhood usage. Try tests at different times of day. Evenings are usually the worst.
  • Worst case, try a VPN service like Tunnelbear. If that fixes the problem then there's something wrong with your ISP's networking.

posted by Nelson at 10:33 AM on September 25, 2017 [4 favorites]

Does your speed get better after you turn your router off and on (fully unplugged)?
posted by dilaudid at 10:35 AM on September 25, 2017

It's going to be a little trickier to test due to your setup being the combined modem/router, but here's my general troubleshooting list to make sure it's my internet service and not my home blocking the signal or a bad piece of equipment:
  • Unplug everything else from the router, leaving only one computer connected via network cable. Since you have wifi built-in, see if you can disable it temporarily to rule out some unruly device.
  • Go directly to a speedtest site, and if it's one that lets you connect to different servers (speedtest.net usually offers several) try multiple to rule out one bad hop on the internet
  • If you can, do this at a few times during the day. If evenings and weekends are significantly slower, it might be that your internet provider is saturated at some point. It's generally less of an issue now, but cable companies have been known to have more of a shared bandwidth model when it comes to neighborhoods, and communicating this information might be a way to prod them into upgrading infrastructure.
I'd also check to see if there's a minimum guaranteed download speed in your contract and not just a vague "up to" phrase. It may also be that the speed they indicate is only with the newest equipment. That, among other things, is why with my cable provider I have my own wifi router, which takes that out of the testing mix. Whether or not you can or do buy your own modem depends on how well your provider supports hardware they don't provide.

If it's purely a wifi problem, switching to your own router might help, especially one with better antennas or repeaters throughout the house. For what it's worth, I live in a smallish 1.5 story house similar to yours and seldom have problems, but I have the last generation of Apple's wifi router which has pretty robust antennas -- I've got it inside a cabinet and have no issues using a desktop computer upstairs over wifi.

I'd definitely advocate checking DNS settings like Nelson mentioned. The only downside is that in some areas, services that do a location check will get your location wrong and deny you service, but Google DNS generally works well.
posted by mikeh at 11:05 AM on September 25, 2017

Putting aside the question of whether you're getting what they've advertised, 84 Mbps is still plenty fast for most things, and there's no way that speed should be causing things like YouTube to be visibly slow. I believe Netflix says you need 15 Mbps minimum for 4K streaming. So that means that even 5 simultaneous 4K Netflix xtreams would not max out 84 Mbps (assuming ideal conditions and no other overhead, of course, but I think you get the point). You may have some other issue, or a combination of issues, but don't think the raw throughput numbers you're seeing are the direct cause.

BTW, I prefer fast.com over Speedtest. It's run by Netflix and I find it provides a more realistic view of my true connection speed. But I still think you probably have some other underlying issue that's causing both symptoms.
posted by primethyme at 11:13 AM on September 25, 2017 [5 favorites]

How old is your router? Is it on the list of supported models for your cable co? Is there a newer version of it? An old modem/router may not be getting the speeds you are paying for.

Also, it's cable. If your neighbors are bandwidth hogs, you suffer, as it is shared and not dedicated speed.
posted by caution live frogs at 11:23 AM on September 25, 2017

To go from megabits/s to megabytes/s, don't divide by 8 (the naive solution). Dividing by 10 gives a more realistic answer, and take about 90-95% of that as perfect.

Megabits/s is the raw rate of the line, on top of that you layer some sort of physical layer (ethernet), some IP layer, some TCP layer, then you get interframe silence and VLANs and QoS and all of those layers make 10 Mb/s == 1MB/s a much more reasonable number.

If you have a 10Gb line, that's about 1GB, and if you get 950 to 980 MB when the two machines are directly connected... you're doing good.

TL;DR: use 10 bits/byte instead of 8 bits/byte as a better approximation.
posted by zengargoyle at 11:23 AM on September 25, 2017 [1 favorite]

If your neighbors are bandwidth hogs if the ISP is underprovisioned. Part of why gigabit Internet is such a lucrative market is they know they can get away without actually selling anywhere near a gigabit of Internet to every customer. Most customers are limited to 100Mbps ethernet and/or WiFi (10-200 Mbps in practice). And then most customers don't use their Internet all that much. But when everyone watches Netflix at night it goes to shit.

(Speaking from personal experience now in Berlin; my Internet tops out at 80Mbps but it's 9pm so is currently more like 3Mbps.)
posted by Nelson at 12:02 PM on September 25, 2017

Everyone's talking about making sure the cable guys aren't screwing you but

4) I’m willing to throw a little money at new modems, routers, extenders, or a monthly business type plan, but I need some nudges in the right direction. I’ve done some research about improving the network strength upstairs but if it’s overall lousy there’s no point.

is far more promising. You're running a whole heap of stuff through what is probably a garbage wireless modem that doesn't support the latest wifi stuff that makes the PHY rate reasonably fast. If you've got some piece of shit 300n router then yeah, no shit the ultimate speeds are in the 80mbps range.

So if you want the easiest, most proven, and cost-effective solution? Netgear Orbi. They have two sets of radios. One to broadcast wifi with, the other to work as backhaul. They're brilliant little devices for keeping bandwidth high over large coverage areas for someone that doesn't want to rip down their walls.

If you want the *professional* stuff, the last generation UniFi AP is some bulletproof gear that's very competitively priced. But you'll have to wire your house with ethernet to all of the places where you're putting APs (probably three) to get good results. But they *will* be awesome results.
posted by Talez at 12:21 PM on September 25, 2017 [1 favorite]

You can check and see if your wireless internet is going through a crowded channel. There are lots of free apps on your phone that can show you how crowded each channel is. I've used something called Wifi Analyzer. You probably want to use channel 1, 6 or 11, but if you're on 11 and it's full of other people, maybe switch to another. You can do that via your administrative gateway -- it might be written on your modem or your cable provider might've given you the address for it, but it's usually something like

The signal can be weaker the further you get from your modem. I lived in a small one-bedroom apartment and my wifi would slow to a crawl when I was in the bedroom. It made no sense. Anywhere else in the tiny-ass apartment, wifi worked fine. I never did anything about it, but I think you can get a signal booster.

I wouldn't rule out that there is just a problem with your modem or your set up that will require you to call your cable company. I was having an issue with my internet going out constantly so I got Comcast to look at it after several calls where they falsely tried to tell me there were outages in my area. The technician said he changed the port my cable line hooked up to within my apartment building and he also replaced my modem. One of those things fixed the problem.
posted by AppleTurnover at 3:08 PM on September 25, 2017

Wireless interference. https://www.howtogeek.com/209450/how-you-and-your-neighbors-are-making-each-other%E2%80%99s-wi-fi-worse-and-what-you-can-do-about-it/
posted by GiveUpNed at 3:59 PM on September 25, 2017

If you have plaster walls of that age, it's very probable the plaster is on some kind of metal lath which is a lot like heavier-gauge chicken wire, which will attenuate the signal significantly whenever it passes through one of these walls. As an experiment, I'd see what kind of speeds you can get 1. in the same room as the router with no obstructions. 2. If one of these laptops has a wired ethernet port, try hooking it up to one of the router's "LAN" ports directly (you may have to disable wireless on the laptop temporarily to be sure it's using the wired port.)

#1 will take the walls out of the problem, #2 will take the wireless out completely. If one or both of these work great, it's not the cable provider's connection.

If these test good, it's likely that you need something more substantial to cover this much square footage + attenuating walls.
posted by mmagin at 4:04 PM on September 25, 2017

Lots of good advice, above.

Have you made sure that your network security is good, and no one has popped your router and is running extra stuff through it? Patch its firmware, disable uPnP, and the like.

Also, do you need to add a second wifi router to your house (with a wired backhaul to your first router) to improve coverage? I live in a house from 1985, and my wifi router is in on far corner of the ground floor. I had a wire for the Roku in the family room at the far end of the house, and this past weekend I swapped in our old router to have a good signal at that end of the house. (I can't roam and have the connection follow, but that's a small price to pay for better signal strength & speed.)
posted by wenestvedt at 7:50 AM on September 26, 2017

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