[SOLVED] Wifi Speed Fluctuates

[sagich_dochnicht]

Hi, I already posted about my problem on reddit, but nobody there was able to really help me. Here is the original question from my side; I added everything I've learned at the bottom of this post. As the reddit thread might include some other useful information, here is the link for it: https://www.reddit.com/r/wifi/comments/abuef0/wifi_speed_fluctuates/


As the title says, my internet speeds are fluctuating A LOT in a short period of time. Sometimes I get 30+ Mbit/s, half a minute later they're at <1 Mbit/s. There are lots of devices connected in the household, but the drops seem to be too big to be simply down to a lot of devices. When the download speed is so low, the upload speed still stays quite high (~10 Mbit/s probably); no idea if that means anything.


It started about 1-2 months ago without any changes made to the network. There are different access points in the house, the problem occurs being connected to all of them and on multiple devices (2 laptops, 1 Android phone, 1 PlayStation 4).


In forums and other threads I found out that interferences are a common cause for fluctuating wifi, therefore I switched to 5 GHz only on the AP I use the most. In the screenshot I attached you can see all the other networks around; all of them are on 2.4GHz. This didn't fix the problem, but only made my connection worse (I assume it's because the AP is behind a wall and 2.4 GHz passes through walls more easily).


So to summarize:

-) it suddenly started to fluctuate

-) it's most likely not down to interference

-) it's most likely not down to the devices connected to the Wifi

-) it's most likely not down to the APs


Screenshot explanation:

green -> APs in the network

"Durchs..." -> average

Kanal -> channel

Breite -> block size (20 vs. 40 MHz steps)

Anbieter -> AP manufacturer

I tested the speed with both speedtest.net and Google's speed test

Edit:
-) I performed a test at dslreport.com that indicated a bufferbloat problem:
-) I performed a iperf test that showed fluctuating network speeds: https://i.imgur.com/a7Qs0p7.png[/img]


I would really appreciate your help; as you can see, I'm really not an expert and I'm really unsure what all these results mean.

Edit 2: My router/modem seems to be a ISP branded technicolor TG588v

 

[bill001g]

So why do you not think it is interference have you tested to be sure.

It is a pretty easy test you connect via ethernet and see if the problem goes away.

It tends to be a waste of time troubleshooting problems when you dismiss the most common cause of a problem like this...ie wifi interference.

Once you have proved or disproved that it is the wifi you can look at how to solve the problem.

 

[sagich_dochnicht]

So why do you not think it is interference have you tested to be sure.

It is a pretty easy test you connect via ethernet and see if the problem goes away.

It tends to be a waste of time troubleshooting problems when you dismiss the most common cause of a problem like this...ie wifi interference.

Once you have proved or disproved that it is the wifi you can look at how to solve the problem.

I switched the AP to 5GHz and checked for other 5GHz networks, but there are none my laptop can detect (as can be seen in the screenshot). Shouldn't that eliminate the possibility of interferences?

 

[bill001g]

All your laptop can see are routers that transmit their ssid. It can not see the actual end devices that are send and receive the data and it is this traffic causing the problem. There are also devices like phones, security cameras, baby monitors etc that operate on the same radio frequiencies but do not use WiFi do you laptop can not detect them.

And finally the laptop only identifies the channel that the router is sending the ssid broadcast on. The communication is actually using blocks of 4 channels on the 5g band and around 6 on the 2.4g band. It is impossible for 2 routers to coexist on the 2.4g band when they are running at the higher encoding rates. There is only 60mhz of bandwidth and a single router uses 40mhz so it is impossible to fit 2.

But hey if you are sure it is not interference just go blindly buy a new router or new nic card and see if the problem goes away.

You really want to be sure before you spend money or try to tell the ISP they have a problem. They will correctly claim you can't prove it is not your wifi.

 

[aditya010]

I am having a similar issue. When I connect my laptop to the router using Ethernet, it gives proper speed. But with Wifi from the same router it's way less speed. I have 100Mbps plan. I get 100Mbps using Ethernet. When connected with Wifi I get 560kbps almost every time. It's always around 500kbps. There seems to be no issue with my laptop hardware because when I connect my laptop using my Mobile phone as Wifi Hotspot, I get the expected speed, around 10mbps.
To sum up, all the devices at my home are getting proper speed using the same Wifi except my laptop. But my laptop gets that same proper speed only with Ethernet connected to the same router. And my laptop gets proper speed when connected to other Wifi networks.
That should mean My laptop is fine. I am not sure if there is any problem with the router.
Also, there are very short duration of times during the day when this issue is resolved but most of the time, I face this issue.
This is so weird, I'm trying to figure out the actual problem but found nothing.
I reinstalled and updated my laptop so many times.
The router is responding fairly to other devices connected to it, wirelessly.
What could be the possible problem? How to diagnose?
Please help me if you can. I'd really appreciate any kind of help.

 

[kanewolf]

This is a two year old thread that is solved. Do not hijack an old thread. If you have a problem start a new thread.

Thread closed.