Fast upload but abysmal download

[aeridith]

Hi there,

Getting extremely good speeds uploading (1200Mbps) via speedflex but bad speeds when uploading(350Mbps). Any idea what the culprit could be?

Source device: iPhone 13 802.11ax WIFI-6

Destination: Ruckus 750 with 802.3at 

Cheers,

Aeridith

[DarrelRhodes]

846Mbps would be incredible, regardless of the internet speed!

Further details here: https://support.apple.com/en-gb/guide/deployment/dep268652e6c/web on iPhone capabilities, please remember that PHY rate is the. same as data rate and does not equate to TCP throughput, which is usually 40-60% of the PHY rate (depending on lots of factors!).

Best,
Darrel.

[aeridith]

Thanks @DarrelRhodes !

I actually went to that page and saw that iPhone 11 and later has 1200 Mbps Maximum PHY. If I use iperf3, I'm seeing ranges of 791 Mbit/s download and 737 Mbit/s upload so based on your math that means I'm getting great speeds.

After seeing other posts - I agree with your assessment that the speedflex tool is inaccurate. I'm currently trying to track down network gremlins (video conferencing, cameras, WIFI calling, zeroconf are all having wildly different behaviors).

One of the less talked about issues is background chattiness on the network. I'm sitting in front of the router with WIFI 6 and I see ping rates like this - I can't help wonder if there is a relation between the issues above and these ping results. BTW CPU is 3% with 2 as the load on a macbook pro.

64 bytes from 192.168.250.1: icmp_seq=17 ttl=64 time=2.027 ms
64 bytes from 192.168.250.1: icmp_seq=18 ttl=64 time=1.637 ms
64 bytes from 192.168.250.1: icmp_seq=19 ttl=64 time=41.165 ms
64 bytes from 192.168.250.1: icmp_seq=20 ttl=64 time=86.733 ms
64 bytes from 192.168.250.1: icmp_seq=21 ttl=64 time=128.615 ms
64 bytes from 192.168.250.1: icmp_seq=22 ttl=64 time=172.465 ms
64 bytes from 192.168.250.1: icmp_seq=23 ttl=64 time=219.487 ms
64 bytes from 192.168.250.1: icmp_seq=24 ttl=64 time=1.987 ms
64 bytes from 192.168.250.1: icmp_seq=25 ttl=64 time=13.264 ms
64 bytes from 192.168.250.1: icmp_seq=26 ttl=64 time=3.427 ms
^C
--- 192.168.250.1 ping statistics ---
27 packets transmitted, 27 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 1.637/38.004/221.103/66.654 ms

Am I chasing the wrong thing when it comes to speed and ping?

[Squozen]

I would skip ping and pull out Wireshark to see what chatter you're getting on both the wired and wireless networks. Can you describe the network a little? How many devices?

[DarrelRhodes]

Hi Aeridith,

Thanks for your message. Whilst ping isn't a stand-alone indicator of anything specific, it can certainly play an important part of understanding the full picture of what is happening with the wireless network and underlying environment.

High levels of jitter (ping response time variations) can certainly be an indicator of underlying high levels of interference. I would suggest investigating a change of channels, perhaps implementing ChannelFly and ensuring clients are using 5GHz where possible.

[Squozen]

I have the results right here. 😀

Original iPhone test: https://www.speedtest.net/my-result/i/5117165449

iPad test from a few minutes ago: https://www.speedtest.net/my-result/i/5125264400

2015 MacBook Pro - https://www.speedtest.net/result/d/431706937

The datacentre I'm testing against is only 12kms from my house and I'm on 1000/200 fibre.