Google Wifi very slow download speed

[pedroportari]

I have a Google Wifi mesh with three devices since 2019. During all this period, the mesh performed amazing. No problems with connectivity or Internet speed. Unfortunately, last week, i lost the connection and my wi fi wasn't working at all. After checking possible problems, I discovered that my download speed was very slow, while the upload was perfect, with normal rates. I ran many speed tests and the results were all the same:

Download speed: 1Mbps

Upload speed: 90Mbps

This is very strange, since my download should be around 500Mbps. I don't know what is happening and what are the possible causes for this problem. Coul you please help me with the issue?

Thank you in advance,

Pedro

[PatrickP_Viking]

Hey @pedroportari .

Can you elaborate more on the "connection loss" and what specifically has been done to troubleshoot? Has anything changed with your ISP or setup? What ISP and service do you have?

I have some ideas on what is happening but I need some additional details to narrow it down better.

[pedroportari]

Hi Patrick! Thank you for your prompt reply and sorry for the delay to answer you.

So, the "connection loss" in fact was the extremely slow download speed. The download speed was so slow that I thought that the connection was lost, but in fact it was just the download speed that was very low. Please disregard the "connection loss" point. The fact is: 

I discovered that my download speed was very slow, while the upload speed was perfect, with normal rates. I ran many speed tests and the results were all the same:

Download speed: 1Mbps

Upload speed: 90Mbps

Remembering that my "normal" download speed ia about 500 Mbps.

To try to troubleshoot I've just factory reset the devices. But nothing happenned, still same problem.

Answering your other questions:

Nothing has changed with my ISP and setup. By the way, what exactly do you mean by "set up"?

My ISP is Claro NET. I'm from Brazil, so this is a service provide here. You are probably not familiar with this ISP.

Could you please help me? What do you have in mind to solve my problem?

[PatrickP_Viking]

Hey @pedroportari .

By "setup" I mean how is the network connected from the ISP to a connected device.

Also, can you detail how you are running the speed test (I.e. from what device/app)?

[pedroportari]

Hi Patrick,

I'm not quite sure that I understood what you said, but my network is connected from the ISP to a connected device through the Google Wifi. Is this about what you were talking?

I did two simple speed test:

- The first one was through the site: https://www.speedtest.net/

- The second test was carried out within the Google Home application itself. Within the application, a speed test option is available and that is what I used to check my internet speed.

Finally, the speed measured in the tests was the same. Both for download and upload, which are the values already informed in the messages above.

What do you have in mind that could be the problem?

[PatrickP_Viking]

Hey @pedroportari .

This example of a network using Spectrum internet is what I mean by network setup:

Spectrum cable from street > modem > Nest Wifi Pro > switch > point > devices

What does your setup look like? I suspect that the issue may be related to a Double NAT but without knowing the setup it is difficult to say if it is in play or can be eliminated.

[pedroportari]

Hi Patrick, 

What do you mean by "switch" and "point"?

In my view is just: 

Spectrum cable from street > modem > Google Wifi > devices. This is my setup.

I can't understand why there would be intermediaries between Google WiFi and the devices connected to it.

[PatrickP_Viking · Accepted solution]

Hey @pedroportari .

This article explains the connections better for clarity: Hardwire Nest Wifi Pro, Nest Wifi, or Google Wifi with Ethernet 

When you did the resets, did you also reset the modem and have it reprovisioned afterwards by the ISP? Do you know the make/model of the modem?

If you have not tried this troubleshooter, please try this also:

Nest Wifi Pro, Nest Wifi, or Google Wifi network not working

[pedroportari]

Hi Patrick!

Thank you so much for your explanation. Now I see what you were saying about setup. Therefore, my setup is:

Spectrum cable from street > modem >  Google Wifi Router (In NAT(Standard) mode) > 1st point (In bridge mode) > 2nd point (In bridge mode) > Devices.

I have already reset the modem and after that, everything went fine: No change in performance. Both the modem and the Google WiFi situation.

The make and model of the modem are, respectively: 

Make: Sagemcom

Model: F@st 3895

Furthermore, after you mentioned the double nat problem, I started researching more on the subject. The recommendations I found said that the solution to this problem was to put the WiFi router that comes within the modem provided by the ISP in "Bridge Mode". Yesterday, I tested this solution. The results were:
Download speed: 0.7 Mbps
Upload Speed: 90 Mbps

As you can see, not much changed in the performance result.
I'm taking a quick look at this link you recommended and I'll give you an answer soon.

After this new scenario that I'm giving you and after this news, do you have any other recommendations for me or any idea what's going on?

Best regards

[PatrickP_Viking]

Thanks @pedroportari for the additional details.

I did some research on the modem you mentioned and that is likely the cause of the slow speeds. That is a router/modem combo similar to one they use in the states. 

Try these steps:

1. Disconnect the Spectrum gear from the Google Wifi
2. Perform a reset on both devices and then remove the power cord for the Google Wifi only
3. Plug an Ethernet cable into the modem and navigate to the Spectrum portal's self-service installation/provisioning site and request the provisioning signal be resent. If the self-service isn't available, you will need to contact Spectrum Support to have them do this.
4. Once provisioned, access the modem's UI and do the following:
   • Disable routing (may not be an option)
   • Disable Wifi
   • Place in Bridge Mode
5. Connect the Ethernet cable to the Google Wifi from the router/modem combo and perform the normal setup steps.
6. Check download speeds from the Google Home app

These steps should either solve it or give us an idea where the issue is occurring. When you perform a SpeedTest.net test it is measuring the speed of the device you are running the test from so speeds will be lower than the subscribed speed due to the different jumps and gear it has to deal with. When you run a test from the Google Home app it is testing the speed directly from the ISP to the Google Wifi.

The issue appears to be due to a Double NAT situation. The Spectrum gear and Google Wifi are both trying to manage the traffic which is resulting in the slow download speeds because of the conflicts. The only other culprit would be a setting but it wouldn't cause the dramatic drops.

I had Spectrum for over 10 years and never had speed issues because I used my own compatible modem only and separate router. I recently switched to GFiber and get the expected speeds without having to change anything with the Nest Wifi Pro I already had. ISPs tend to make it harder than it should be to use your own equipment because they lose the monthly "rental" fees for using their gear.

Let me know if you are able to get it resolved with the above.

[shyh]

Experiencing the same issue here. Connecting directly to the service provider's modem results in expected fibre speed (650+mbps), switching to Google wifi mesh results in it being throttled to ~85mbps

[PatrickP_Viking]

Hey @shyh .

If you have not tried this troubleshooter, please try this also:

Nest Wifi Pro, Nest Wifi, or Google Wifi network not working