Hi all

We have recently upgraded our network to SXT-G units in a hope to solve a speed issue but without any luck. We are getting a huge drop in TCP throughput on each hop to the point where it is causing speed issues for clients on the end of the line.

Things we have found out by testing and general background
-It’s not frequency related. We have tried multiple frequencies in different bands.
-UDP traffic goes at over 130Mbps from one end to the other so its not an old 10/100 interface somewhere.
-All links are negotiated at 270-300Mbps with a CCQ of 90-95+%
-NV2 is in use for all hops.
-One end of the hop is in Bridge Mode. The other is in Station Bridge mode.
-Ethernet/Wlan is bridged on the SXT-G units.
-RB750/RB2011 is in bridge mode (NAT is done on the client SXTs themselves)
-TCP throughput is determined by visiting speedtest.net. Mikrotik Btest confirms low throughput on TCP mode when going from router to router.
-The problem existed with plain SXT units before the upgrade. The upgrade has not solved the problem

Does anyone else have a network of SXT-G units and has the same problem? Any input will be very welcome.

Thanks. Jon

its common to have a really big drop in troughput when going from ptp to ptmp.

PS! 5825 is not ideal freq for Your sxt. Check the antenna pattern, that is really "Sharp" around 55xx (and will have about 10db better signal here, than 5700)

Thanks samsung172

The odd thing is im loosing quite a bit of speed before it even gets to the omni?

With your advice is is best to keep SXTs out of the 5.7-5.8Ghz band then? Would RB711s be better with stationboxes from RFelements?

Jon

When you test the first link, do you connect between the second SXT and before the RB2011? Or do you test through the RB2011?

Have you turned off the all mangle and queue tree rules on the RB2011?

I have difficulty getting much over 100Mbps through my RB493Gs with our mangle / queue tree rules. I just run out of CPU.

I only have one RB2011 in the field. It's CPU utilization seems very similar to the RB493Gs.

Thanks samsung172

The odd thing is im loosing quite a bit of speed before it even gets to the omni?

With your advice is is best to keep SXTs out of the 5.7-5.8Ghz band then? Would RB711s be better with stationboxes from RFelements?

Jon

You have to read doc's from each antenna.


http://routerboard.com/pdf/318/sxt-patterns.pdf

As you can se, when horizontal freq is at max, the vertical drop a bit Down. When vertical is at top, the horizontal get Down. but look at what happen if you change to 5180 or 5750, or wors, like Your setup, 58xx.

edit : Also take a look at the off center pattern to hor/vert . It is impossible to get this Perfect. as if horizontal is aligment 100%, vertical is a bit off center. And vica versa.

Hi lambert

The ports are bridged so technically the RB2011 is a giant switch. The connection was tested through the RB2011 but i will attend site and test again via connecting direct to the SXT.

All CPU load is normal. I monitor the system via the dude and have never seen the CPU rise above 30% on any device in the system.

samsung172
Thanks for that. I will look at some RB751's + external antennas that can do 5800ish