Wireless Access

Hi, 
I'm trying to compare the wireless performance of the aruba AP 505 in a controller based environment with the performance of the wired connection (in both the cases the cables are up to 1Gb).
I found an interesting result: with one TCP stream on iperf3 i found a throughput of around 300Mbps, while with multiple streams the throughput is around 600-700Mbps.
Instead, with the wired connection I found always a throughput of 900Mbps both with one or more streams. 
Do you know why in the wireless case there is this big difference that is not present in the wired case?
In all the cases my iperf server is a workstation in the local network with 1Gb interface and so the problem is not due to the iperf server.

• I attach below the results (as sais 300Mbps and 650Mbps are obtained with wifi, while the two 940Mbps results are obtained with the wired connection).
• Is it possible that the difference is given by the packet loss and the relative TCP windows size? In the wired case the result is the same with 1 or more streams, while with wifi it is very different. Can you explain me this big difference?

Hi,

Wireless is working on half duplex, not full duplex as wired ethernet network.

When you have data rate like 800mbps on wireless your actual data throughput is near half because of wireless L2 connection overhead.
Wireless actual throughput is depends on many factors, as Client device types and capabilities, environment and etc. you can find tools on internet how to calculate.
Original Message:
Sent: Jun 29, 2022 03:50 AM
From: Matteo Piva
Subject: Wifi TCP iperf throughput: 1 stream vs multiple streams with very different throughput

Hi, 
I'm trying to compare the wireless performance of the aruba AP 505 in a controller based environment with the performance of the wired connection (in both the cases the cables are up to 1Gb).
I found an interesting result: with one TCP stream on iperf3 i found a throughput of around 300Mbps, while with multiple streams the throughput is around 600-700Mbps.
Instead, with the wired connection I found always a throughput of 900Mbps both with one or more streams. 
Do you know why in the wireless case there is this big difference that is not present in the wired case?
In all the cases my iperf server is a workstation in the local network with 1Gb interface and so the problem is not due to the iperf server.

• I attach below the results (as sais 300Mbps and 650Mbps are obtained with wifi, while the two 940Mbps results are obtained with the wired connection).
• Is it possible that the difference is given by the packet loss and the relative TCP windows size? In the wired case the result is the same with 1 or more streams, while with wifi it is very different. Can you explain me this big difference?