Okay..
We have been doing quite a lot of network testing lately, because I've been experiencing slow upload speeds.
First of all we did go to our ISP (local ISP, so the support is simply AWESOME!) and told them about the issue and they assured their settings were right and that we got high priority on their network and a speed of 25 / 25mbit. (fibre network)
So then we started troubleshooting, we ended up with me turning my DIR-655 A3 (firmware 1.11) into a access point instead of a router as it has to be connected to our D-Link DVG-5802 router / gateway anyway, so no need for double NAT'ing!
Both the DVG-5802 and my DIR-655 got the usual speed optimizations, no SPI, no logg, endpoint independent filtering, multicast streams activated, upnp activated etc..
My DIR-655 is connected directly to the DVG-5802 with the use of a 5m CAT7 cable, my laptop is connected through wireless to my DIR-655 (N-only mode with WPA2 / AES only! running a Intel WiFi 5100) and my other computer uses a Intel Pro/1000 PT Desktop dedicated NIC adapter with a 3m CAT7 cable!
We were using SpeedTest.net with the recommended and closest server, the closest one is actually hosted by Hafslund Telecom whom are the same company as our ISP!
I got the same results with both my laptop (20cm from the router) and my other computer running CAT7 cable. The results were: 28mbit down to 16mbit down-speed (mostly around 20-18mbit, and never above 10mbit up-speed! Mostly 9-8mbit.
We ran the test like hundred times, without any other computers using our network. We tried it in the morning, mid-day and evening and repeated it a few days in a row, but with the same results.
Then we tried to connect my laptop directly to the DVG-5802 using wireless.
Note that the DVG-5802 is running B / G - mode (no N - mode whatsoever) and WPA AES / TKIP only, along with it having only two antennas. I was also sitting 5m away from it with a wall in-between, so the conditions should be much worse compared to when connected to my DIR-655.
And for some reason my down-speed is much more stable? Not dropping below 20mbit whatsoever? Mostly it is 26-24mbit compared to using cable with my DIR-655 resulting in mostly 20-18mbit.
And the upload speed didn't drop below 20mbit either?! That's twice the upload than through my DIR-655? It's mostly synchronized with the down-speed making it mostly 26-24mbit, and that's way better than never going further than 10mbit through the DIR-655?
I tried to re-connect to my DIR-655, also using my other computer with cable at the same time as I got these results when directly connecting to the DVG-5802, and through the DIR-655 the results were simply worse, more unstable and slight lower average down-speed and half the up-speed?
How is this possible? Even when sitting several rooms from the DVG-5802, with multiply walls in-between my laptop and the DVG-5802, and it running B / G - mode with WPA TKIP / AES I've got a stable 16-18mbit up-speed? Something is clearly going wrong with the up-speed when it goes through the DIR-655? Why is this?