Improve speed on nearly perfect connection

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Improve speed on nearly perfect connection

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Improve speed on nearly perfect connection
Improve speed on nearly perfect connection
2015-12-20 00:30:22
Model :

Hardware Version : Not Clear

Firmware Version :

ISP :

Hi,
I am using two CPE510 to connect a server in another building over a distance of 30m with clear vision. The SNR is better than 70dB.
The speed test tells me that I get a bit less than 70 MBps. RX rate and TX rate are 300 Mbps. With 50 % overhead I would expect 150 Mbps net.
Where is the bottleneck here?
If the bottleneck is the LAN connection, is there a way to use the second LAN port?
My server has serveral LAN ports and supports bonding.
Thanks
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#1
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Re:Improve speed on nearly perfect connection
2015-12-21 08:57:08
Hi
1. Wireless devices work in half-duplex so for 300Mbps product CPE510, the highest transmit rate is 150Mbps.
2. This rate is a physical speed. Remove the expenditure of control/management frame in 802.11, and encapsulation from underlying to upwards, the actually data rate is no more than 100Mbps.
3. Other factors such as long distance and radio collision lead to a lower speed. 70Mbps is a good status.
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#2
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Re:Improve speed on nearly perfect connection
2015-12-21 10:11:35
You

rudi wrote

distance of 30m with clear vision.
Where is the bottleneck here?

Have you made tests lowering the power on both CPEs distance of 30 mts. it's to short, if that does not solve the issue, lay cable and test
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#3
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Re:Improve speed on nearly perfect connection
2015-12-21 15:34:16

stupidbird wrote

Hi
1. Wireless devices work in half-duplex so for 300Mbps product CPE510, the highest transmit rate is 150Mbps.
2. This rate is a physical speed. Remove the expenditure of control/management frame in 802.11, and encapsulation from underlying to upwards, the actually data rate is no more than 100Mbps.
3. Other factors such as long distance and radio collision lead to a lower speed. 70Mbps is a good status.


I did not know that wifi works in half duplex. So 100Mbps duplex is what you can get with 300Mbps wifi connection. More test with iperf showed that I get around 90 Mbps. I only wanted to confirm that the wifi is the bottleneck here and that using 2 ethernet ports will not improve the speed.

The receiver in the CPEs seems to be very sensitive. I had to lower the transmitt power to 0 dBm to get best performance.

It takes a while after rebooting the CPEs until the connection get established (I guess the reason is the DFS requirement on all channels in Germany) but once estabished it seems to be rock solid like a cable.
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#4
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Re:Improve speed on nearly perfect connection
2015-12-21 16:10:51
Sorry for my mistake. Your test result of 70Mbps is almost the maximum speed for CPE as a result of limited hardware resource.
As you know speedtest has certain request for computing power. For your test it's the maximum computing power of CPE while it still didn't reach the limitation of transmit capacity.
So using two computer for testing, like the below topology:
PC1-----------CPE(AP mode)))))))((((((((((CPE(Client)----------PC2
You can get higher speed like 90Mbps. Theoretically you could get 100Mbps even 150Mbps. But since the LAN port of CPE is 100Mbps port, you get 90Mbps at last.
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Re:Improve speed on nearly perfect connection
2015-12-21 17:35:02

stupidbird wrote

Sorry for my mistake. Your test result of 70Mbps is almost the maximum speed for CPE as a result of limited hardware resource.
As you know speedtest has certain request for computing power. For your test it's the maximum computing power of CPE while it still didn't reach the limitation of transmit capacity.
So using two computer for testing, like the below topology:
PC1-----------CPE(AP mode)))))))((((((((((CPE(Client)----------PC2
You can get higher speed like 90Mbps. Theoretically you could get 100Mbps even 150Mbps. But since the LAN port of CPE is 100Mbps port, you get 90Mbps at last.


Yes, I figured that the CPE cpu was the limit in my first tests. So I used iperf on PC1 and PC2 in the test setup.

Your statement suggests that it might pay off to bond 2 100Mbps ethernet ports if the 100Mbbps port is the bottleneck in my setup. Any idea to do this with the stock software or do I need to switch to some open source alternative?
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Re:Improve speed on nearly perfect connection
2015-12-21 17:57:46
So you want to bond the two LAN ports on CPE? The present firmware must doesn't support. How about a third party software I don't know.
But I think using a third party firmware is not recommended. You want to try this for some special requirement?
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#7
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Re:Improve speed on nearly perfect connection
2015-12-21 21:12:33

rudi wrote

or do I need to switch to some open source alternative?

Before make sure you are able to use Recovery mode here http://forum.tp-link.com/showthread.php?81684-How-to-use-firmware-recovery-function-of-Pharos-CPE I can only recover with Win 7 no luck with Win XP or 10
Try OpenWrt Snapshot, and if you need LuCi opkg install, only upper channels work, CC bin. does not work
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Re:Improve speed on nearly perfect connection
2015-12-22 15:50:32

danymarc wrote

Before make sure you are able to use Recovery mode here http://forum.tp-link.com/showthread.php?81684-How-to-use-firmware-recovery-function-of-Pharos-CPE I can only recover with Win 7 no luck with Win XP or 10
Try OpenWrt Snapshot, and if you need LuCi opkg install, only upper channels work, CC bin. does not work

I did recover one of my CPEs using my ubuntu server running atftp server. No problem.
What is CC bin? Compiler? I would need to setup a cross compiler on my linux box, doable.

I would like to maximize the speed as the threat suggests.

So far the answers suggest that the bottleneck is in fact the LAN interface. Since the cpu is too weak to prove that the wifi speed is higher as my experiments and stupidbirds comment suggests the only way to prove that the LAN is the bottleneck is to improve the LAN. The only way to do that is to use the second port. If one can bond them one can make practical use of it if the server and the switch suport bonding (managed switch).

If it would work then it will almost double the speed in my application but it would also be very usefull for an AP in a multiple client setup. In this setup the LAN of the AP would limit the performance. Investing in a switch and an extra cable would be all what is needed to almost double it.
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#9
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Re:Improve speed on nearly perfect connection
2015-12-22 21:08:55

rudi wrote

What is CC bin? Compiler?

CC is Chaos Calmer, a Bin, it's buggy, use a Snapshot (Trunk) comes without interface, if you need it, download LuCi and uhttpd-mod-tls, but only upper Channels work.
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#10
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Re:Improve speed on nearly perfect connection
2015-12-23 15:34:20

danymarc wrote

CC is Chaos Calmer, a Bin, it's buggy, use a Snapshot (Trunk) comes without interface, if you need it, download LuCi and uhttpd-mod-tls, but only upper Channels work.

I can only use Channel 100-140 if I select Germany in the original software. I guess there is a legal restriction to these channels here.

Any idea if the following setup would work with the original software?

........... CPE 510-1 ...........CPE 510-2
PC1 ------------LAN0 ))))) ((((( LAN0----------- PC3
PC2 ------------LAN1 ))))) ((((( LAN1----------- PC4

All ip's on the same subnet.
If it would work one can test if bonding of LAN0 and LAN1 can improve the performance.
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#11
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