@tanveer2137 

 

Yes, these test results point strongly to Ethernet cable at the 3rd location. Main Deco can establish Ethernet link, but unable to negotiate speeds faster than 100Mbps.

 

If you have device with gigabit Ethernet card, such as PC or laptop, you can connect it with Ethernet cable to the second port of Deco at the 3rd location and run speed test on that device over wired connection. But this is optional, as test results you have are sufficient.

 

You will have to replace that Ethernet cable.

 

Before you do, try this: unplug Ethernet cable from both ends and plug tightly back to the different Ethernet ports of Deco and Archer Router. That will not fix issues inside cable, but once at my house this is all I needed to do to restore gigabit link between my Deco and my router. It appers Ethernet cable at my house became slightly loose at Ethernet port, unplugging and plugging it back fixed the problem. Interestingly, link didn't fail completely, it still operated at 100Mbps.

Thanks for all the feedback. I will try to check the ethernet cable ends on both the router and Archer and switch them out. Problem is, if it is actually the cables, that might a difficult task to change since all cables run through the apartment walls. Also, what about 2nd Deco. It is getting good speed but still not the same as the main deco. Shouldn't they get the same speed?

  @tanveer2137 

 

It is possible there is additional WiFi interference near 2nd Deco, which impacts speeds. A fridge, microwave, something inside the wall or on the other side of the wall that you can't see.

 

I would not worry much about 2nd Deco - if it were on WiFi backhaul, you should have seen worse speeds. Usually not exceeding half of what Main Deco delivers. If 2nd Deco was on Ethernet backhaul with cable that can't negotiate gigabit - you'll see speeds under 100Mbps.

 

Still, because now you know how to run tests, you can repeat the same test but for 2nd Deco: power off Satellites, bring Main Deco to where 2nd Deco is, power on Main Deco connected to Ethernet cable of 2nd Deco and run speed tests there.

 

Depending on outcome of that test:

 

A) If you get same speeds 2nd Deco delivered, my opinion is there must be WiFi interference;

or

B) If you get Main Deco speeds even in that location, keep Main Deco there and move 2nd Deco to where Main Deco was. 

Thanks for the feedback again. I will check the end points of the ethernet cable. Quick question - If the issue is ethernet cable, how come I am getting the same speed (90-92) when I disconnect the ethernet and be on wifi mesh?

  @tanveer2137 

 

I can't explain this. A coincidence? The test with just Main Deco is final, because it can't run without Ethernet link. 

 

I suggested first test, with unplugging Satellite, because it is simple and does not impact your home network very much. Unplug Ethernet cable from Satellite Deco, run few speed tests, plug it back. 

I was confident 3rd Deco does use Ethernet backhaul. My expectation was that after unplugging Ethernet cable either Satellite will fail to connect to the rest of Deco mesh if it is too far from it, or will deliver different speeds. When this didn't happen, I suggested test with Main Deco: it requires more work, but it is more conclusive.

  @Alexandre. 
 

you were right. It was the cable. There was a joint within the cable which I was not aware of. They had to do that to extend the cable. I changed the connectors and its all good now. I am getting the same speed as main deco.

 

Thank you so much for all your help.