Question Getting Very Slow LAN Connection

[salanalani]

I have this strange issue where my LAN connection speed is very slow compared to WiFi speed.

My ISP plan is 400Mbps with Spectrum (via coax).
Coax internet is going to Cable Modem and then Ethernet cable to Wireless Router via WAN port (all provided and setup by Spectrum)

At home, I have pre-wired Ethernet across the rooms connected to a 100/10Mbps Switch. That home Switch is connected via Ethernet to the Wireless Router so Internet can be provided to the other rooms.

See picture below which will illustrate the network setup.

In all Internet speed testing, I am using Speedtest.net app via iPhone or Windows 10 and all with same setting and same target server.

Internet speed test results:

• iPhone --> WiFi --> Wireless Router --> Ethernet --> Modem --> Coax --> Internet = ~370Mbps (which is great).
• PC --> Ethernet --> Wireless Router --> Ethernet --> Modem --> Coax --> Internet = 120Mbps (which is fine but still slow compared to WiFi connected and I don't know!).
• PC --> Ethernet --> Home Switch --> Ethernet --> Wireless Router --> Ethernet --> Modem --> Coax --> Internet = 20Mbps (which is very slow and I don't know why!!!).

I did iPerf testing between two PCs connected to Home Switch and I am getting ~90Mbps which is about right since this is 100/10Mbps Switch, so to eliminate that there is no issue with my Home Switch.

 

[kanewolf]

You show iPerf between Laptop0 and Laptop1. What about Laptop0 and Laptop2 ?

 

[bill001g]

What is iperf between one of those laptop and laptop 2.

There is a public IPERF site I forget the location that you can test from.

Speedtest is affected by the browser. I can't see how it can be 20mbps.

Maybe disconnect the router and hook the pc to the modem directly. It would show if the router somehow is causing this.

............Im a idiot I never hit post

 

[salanalani]

You show iPerf between Laptop0 and Laptop1. What about Laptop0 and Laptop2 ?

iPerf between laptop0 and laptop2 is also around ~90Mbps which about right considering laptop0 is on 100Mbps.

But anyway, I changed that 100Mbps Switch to 1Gbps Switch and problem solved; all laptops now can go up to 370Mbps with Speedtest.net.

Thank you all.