Reaching Almost 600 Mbit/s with 802.11ac

Back in October 2016, I ran my first Wifi 802.11ac speed measurement at home. At my desk with one wall between me and the Wifi Access point plus a nasty corner, I could get up to 368 Mbit/s versus a ‘measly’ 70 Mbit/s with my 802.11n based Lenovo X230 notebook I had at the time. What I didn’t do back then was to note the top speed I could get when I was closer to the Wifi access point. Now that I’ve upgraded to a Lenovo X250 with an 802.11ac Wifi card built-in and supporting access points popping-up in many places, it was time to see what the practical maximum could be.

Again I was quite surprised to see the result. This time around I was using a Linksys 1200AC running Lede/OpenWRT and my place of work is around 4 meters away from the Access Point with line of sight. In this configuration, my maximum download speed I could achieve with my Lenovo X250 and the built-in Intel 7265 Wifi card was 600 Mbit/s. Not bad for an 80 MHz channel! In the uplink direction I could reach around 400 Mbit/s. Quite phenomenal values, even more so as the Internet connection behind it is ‘just’ 100 Mbit/s downlink and 40 Mbit/s in the uplink direction. Far from what is possible over the Wifi air interface. Time for an upgrade…

And here’s the iperf3 output with the iperf3 server having been run directly on the Linksys access point:

$ iperf3 -c 192.168.1.1 -R -p 5201

Connecting to host 192.168.1.1, port 5201
Reverse mode, remote host 192.168.1.1 is sending
[ 4] local 192.168.1.248 port 37772 connected to 192.168.1.1 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.00 sec 65.9 MBytes 552 Mbits/sec 
[ 4] 1.00-2.00 sec 71.7 MBytes 602 Mbits/sec 
[ 4] 2.00-3.00 sec 71.2 MBytes 597 Mbits/sec 
[ 4] 3.00-4.00 sec 71.9 MBytes 603 Mbits/sec 
[ 4] 4.00-5.00 sec 71.6 MBytes 601 Mbits/sec 
[ 4] 5.00-6.00 sec 71.7 MBytes 602 Mbits/sec 
[ 4] 6.00-7.00 sec 72.4 MBytes 607 Mbits/sec 
[ 4] 7.00-8.00 sec 71.8 MBytes 602 Mbits/sec 
[ 4] 8.00-9.00 sec 71.5 MBytes 600 Mbits/sec 
[ 4] 9.00-10.00 sec 70.3 MBytes 589 Mbits/sec


$ iperf3 -c 192.168.1.1 -p 5206

Connecting to host 192.168.1.1, port 5206
[  4] local 192.168.1.248 port 32780 connected to 192.168.1.1 port 5206
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec  40.6 MBytes   340 Mbits/sec    0    512 KBytes       
[  4]   1.00-2.00   sec  47.2 MBytes   396 Mbits/sec    0    512 KBytes       
[  4]   2.00-3.00   sec  48.8 MBytes   409 Mbits/sec    0    512 KBytes       
[  4]   3.00-4.00   sec  49.7 MBytes   417 Mbits/sec    0    512 KBytes       
[  4]   4.00-5.00   sec  49.5 MBytes   415 Mbits/sec    0    512 KBytes       
[  4]   5.00-6.00   sec  49.5 MBytes   415 Mbits/sec    0    512 KBytes       
[  4]   6.00-7.00   sec  51.5 MBytes   432 Mbits/sec    0    512 KBytes       
[  4]   7.00-8.00   sec  53.4 MBytes   448 Mbits/sec    0    512 KBytes       
[  4]   8.00-9.00   sec  51.0 MBytes   428 Mbits/sec    0    512 KBytes       
[  4]   9.00-10.00  sec  50.8 MBytes   426 Mbits/sec    0    512 KBytes