outdoor performance problems on standard mode with V3.x PTP

RouterOS Wireless Networking
1

Hi all,

we have seen performance problems with RB333, RB433AH, RB600 on standard mode with 3.x (last check was on 3.12). We have a WLAN network with a lot of PTP links which are running different MT hardware and software releases.

  1. Some month ago we have changed an RB532 link with 2.9x to RB333 with 3.7. the link has 4km distance and signal quality is 35db SNR. we used standard mode with dynamic WDS. a very good link with traffic up to 13Mbit at 2500pps - some hundreds of customers behind. at first it seemed good and i had no troubles but some hours later (the traffic increases in the evening) i had great troubles. the link throughput was very poor 2-3MBit at max. 1000pps and the packet loss very high. after reboot the link was OK agein. but only few time. i did see some peaks up to 8MBit but then back to poor perfomance again. i did change back to old 532 with 2.9x and everything was fine again.

  2. Two month ago i installed an 3 Hop PTP Link (4km+3km+2km) with RB333 and RB600. Signal 35-40db SNR and nearly no HW packet loss at 48-56 MBps wlan speed. After first performance tests with UDP bidirectional test, we did see a “break down” symptome at the link. The perfomance increased up to 10MBit bidirectional and then it decreased to 2MBit with heavy packet loss (ping) within the link. The link did fall into a state where the performance (real traffic and bw-test traffic too) was very poor. with few load it seemed to be OK.
    We did some tests with differnt channels and optmizations but nothing better.
    Only if we changed to nstreme mode everything was fine ! the throughput was at 15MBit bidirectional and stable. So it looks like an software problem on “Standard Mode” on RB333, RB433x, RB600, … with 3.x releases.

  3. Last weeks we changed some internal links within our network with different load and different signal quality and different distances. all together same problem: on some links troubles after a while on standard WLAN mode depending on traffic and pps. with heavy load there is a very clear difference between “old” 2.9x and 3.x. and it seems that we can stimulate this problem with udp bidirectional bandwidth test. After changing to nstreme everything if fine again. so NOW we install all our PTP links with nstreme and are happy again.

—:
so it seems that there is a problem with 3.x at standard mode. the problem comes with traffic and distance. on desktop tests (with no outdoor distance) everything is fine. maybe there is a timing problem which brings down the performance if heavy load comes on the link and the SW cannot recover.

Has anyone seen same problem ???

Best greetings from Austira !
Dieter

2

All my links are with Nstreme. Even ptmp. Doesnt work without. I don’t know why.

3

I noticed that, but I thought it was because I didn’t have my ack timing right.

Never did get the performance where I wanted it, enabled Nstreme and it worked.

4

Problem is most likely with interference, Nstream handles noise far better than standard mode.

5

Seems like this is a similar issue as mine.. MT doesnt seem to address this as an issue.., and im still damn mad.!!! GRRRRRRRRRRRRRRRRR

http://forum.mikrotik.com/t/client-connection-issues-on-3-x/21401/1

6

hi jwcn,

NO interference, because the devices (e.g. 532 with 2.9x) only are changed against 333/433 with 3.x. Same frequency and troubles. the frequency is clear ! after changing to nstreme its OK again.
this is definitivly a bug within WLAN standard mode on 3.x and distance and traffic (all AND) …

dieterk

7

All I know is there are only a very few people having this problem which does not indicate a widespread issue. There is another underlying problem.

8

jwcn,

we have app 100 PTP links running. we dont use ANY leased lines, we only use WLAN PTPs to carry ALL traffic to our internet customers. and we have many file-sharing clients in the network. so traffic is on main links really very heavy. up to 15-20MBit, 3000pps and more. we have already changed LANCOM L54ag APs to Mikrotik last year (!), because LANCOM has troubles on heavy treaffic :slight_smile: Mikrotik RB532 with 2.9x was much better than LANCOM. but RB532 has CPU limits, so we are changing to RB333, RB433 and RB600 now. But all this new hardware supports only 3.x, so we cannot use 2.9x if we want to get more performance.

so if we change RB532 with 2.9x against RB333,RB433,RB600 with 3.x - all running on standard WLAN mode with exactly same settings (!) at same frequency - we run into explained troubles. But only on heavy traffic and on distance !

So its very clear for me that only few persons have these troubles as i have explained. the same problems i had with LANCOM as we did run into troubles. Most persons never have such stress for the WLAN devices. so few problems are seen and everyone says that this explained problems must have another cause…

good heavens - i have the possibility at Mikrotik to change to nstreme to solve my problems. so i get my performance which i need !

but all i want to say is: dont use Standard Mode with new hardware and 3.x on heavy traffic and distance. you will run into troubles, as long as this real problem is not solved. it seems to be a driver problem or inside OS.

best
dieterk