60km running 5ghz-10mhz - bandwidth question

RouterOS Wireless Networking
1

Hi,

I have a pair of Wrap boards with CM9 cards running 5ghz-10Mhz over 60Km - I have a signal of -70 and can only get a maximum throughput of about 8Mb in each direction. The link is locked in at 36Mbps - any ideas why I am only getting 8Mb

thanks

Rob

2

Seems to me if your getting 8 Mbps across 60km with 5Ghz-10Mhz with a signal of -70 both directions while locked at an air rate of 36 Mbps, then its running as it should.

3

8Mbps full duplex?
then it is ok, and wrap maybe cant handle more.

4

10MHz @ 54Mbits gives performance about 12-13Mbps half duplex (15Mbps with nsteme)
with 36Mbps mode performance is about 2 times worse = 7-8Mbps
You shouldn’t be able to archieve more than that on these settings

5

thanks for that - kinda what I was thinking. I established the link using 10Mhz chanels to assist the link, I shall try it with normal 20mhz channel to see if I can improve the throughput now.

Rob

6

yeah, but probably, you’ll need to switch negotioation rate to 24Mbps (becasue signal on 20MHz is -3dB comparing to 10MHz)
That should give you about 17Mbps simplex
And of course setup nstreme /w polling enabled
framer-policy=exact-size & framer-limit=4000
that’ll speedup connection to it’s limit.

7

With slower CPU boards like the WRAP isn’t it better to run Nstreme with framer-policy=best-fit?

8

no, best fit on high load can cause packetloss
exact-size gives you the best performance

9

Hmm. Is this the same for PTM or just PTP?

10

both, sometimes you can experiment with these settings, but i often set back old values

11