Joined: 02 Feb 2014
|Posted: Fri Sep 04, 2020 2:19 Post subject: Strange WLAN performance
|The WLAN at home is often very slow. The main symptom is web pages taking minutes to be displayed. The wired devices don't have this problem. This wasn't so a few weeks ago (of course, I can't tell what changed).
So I did some crude ping tests with strange results.
This is a partial network diagram:
Huawei box (modem plus WiFi router)
| | |
| | \---Wired computers
| \--- Buffalo DD-WRT (wireless; client mode)
| \-- ipad
\-- phones and wireless PCs
By client mode, I mean https://wiki.dd-wrt.com/wiki/index.php/Client_Mode_Wireless.
I ran ping
- from a wired computer to phones and PCs connected to Huawei
- from Buffalo (command line) to ipad
I used IP addresses. Name resolution is not in the picture.
In both cases, round trip times suck and are wildly erratic. For example between Buffalo and ipad, out of 5 echo requests, best RTT of 1.5 ms, worst 500ms. This is so even if the wireless device is centimeters away from the AP.
Strangely, the very first echo request of each ping command gets a 1-2ms RTT, and all other requests get double- or triple-digit RTTs.
I also ran ping from Wired Computer to Buffalo, and from Buffalo to Huawei. In both cases, RTTs are pretty good: Usually single-digit, with the occasional double-digit exception. Thus the electromagnetic environment seems to be OK. Huawei and Buffalo are 5-10 meters apart with walls between them.
When I switch the Buffalo off, tests between Wired and Wireless devices yield much better results (no triple-digit RTTs). So it has something to do with the wireless connection between Huawei and Buffalo. But what?
In reality, I am very clueless about networking, let alone WiFi technology. So my questions to the community:
- are my tests relevant at all?
- what do they show?
- what other tests would you recommend?