Crazy pings + problems with stability

Hi,

192.168.0.5 64 byte ping: ttl=255 time=10 ms
192.168.0.5 64 byte ping: ttl=255 time=176 ms
192.168.0.5 64 byte ping: ttl=255 time=312 ms
192.168.0.5 64 byte ping: ttl=255 time=3 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=96 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=7 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=262 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=609 ms
192.168.0.5 64 byte ping: ttl=255 time=564 ms
192.168.0.5 64 byte ping: ttl=255 time=362 ms
192.168.0.5 64 byte ping: ttl=255 time=547 ms
192.168.0.5 64 byte ping: ttl=255 time=217 ms
192.168.0.5 64 byte ping: ttl=255 time=5 ms
192.168.0.5 64 byte ping: ttl=255 time=7 ms
192.168.0.5 64 byte ping: ttl=255 time=4 ms
192.168.0.5 64 byte ping: ttl=255 time=5 ms
192.168.0.5 64 byte ping: ttl=255 time=3 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=4 ms
192.168.0.5 64 byte ping: ttl=255 time=6 ms
192.168.0.5 64 byte ping: ttl=255 time=3 ms
192.168.0.5 64 byte ping: ttl=255 time=120 ms
192.168.0.5 64 byte ping: ttl=255 time=170 ms

These are pings from MT to Edimax 7206 working as APC.
Can someone explain me why there are such differences ??

Other interesting thing. When I’m performing ping from SSH console sometimes Winbox console is disconected and other clients connected to AP (MT) has problems with stability…

MT is on RB112 - but workes only as AP. CPU usage is below 10%.

My wlan configuration:

set wlan1 name="wlan1" mtu=1500 mac-address=00:0C:42:15:25:DD arp=enabled disable-running-check=no \
    radio-name="test" mode=ap-bridge ssid="TOLl" area="" frequency-mode=manual-txpower \
    country="united states" antenna-gain=0 frequency=2452 band=2.4ghz-b scan-list=default \
    rate-set=default supported-rates-b=2Mbps,5.5Mbps supported-rates-a/g="" \
    basic-rates-b=2Mbps,5.5Mbps basic-rates-a/g="" max-station-count=2007 ack-timeout=dynamic \
    tx-power=26 tx-power-mode=all-rates-fixed noise-floor-threshold=default \
    periodic-calibration=default periodic-calibration-interval=60 burst-time=disabled dfs-mode=none \
    antenna-mode=ant-a wds-mode=disabled wds-default-bridge=none wds-default-cost=100 \
    wds-cost-range=50-150 wds-ignore-ssid=no update-stats-interval=disabled \
    default-authentication=yes default-forwarding=yes default-ap-tx-limit=0 default-client-tx-limit=0 \
    proprietary-extensions=post-2.9.25 hide-ssid=no security-profile=default disconnect-timeout=3s \
    on-fail-retry-time=100ms preamble-mode=both compression=no allow-sharedkey=no comment="" \
    disabled=no
/ interface wireless nstreme
set wlan1 enable-nstreme=no enable-polling=yes framer-policy=none framer-limit=3200
/ interface wireless manual-tx-power-table
set wlan1 manual-tx-powers=1Mbps:17,2Mbps:17,5.5Mbps:17,11Mbps:17,6Mbps:17,9Mbps:17,12Mbps:17,18Mbps:1\
    7,24Mbps:17,36Mbps:17,48Mbps:17,54Mbps:17
/ interface wireless security-profiles
set default name="default" mode=none authentication-types="" unicast-ciphers="" group-ciphers="" \
    wpa-pre-shared-key="" wpa2-pre-shared-key="" eap-methods=passthrough tls-mode=no-certificates \
    tls-certificate=none static-algo-0=none static-key-0="" static-algo-1=none static-key-1="" \
    static-algo-2=none static-key-2="" static-algo-3=none static-key-3="" static-transmit-key=key-0 \
    static-sta-private-algo=none static-sta-private-key="" radius-mac-authentication=no \
    group-key-update=5m
/ interface wireless align
set frame-size=300 active-mode=yes receive-all=no audio-monitor=00:00:00:00:00:00 \
    filter-mac=00:00:00:00:00:00 ssid-all=yes frames-per-second=25 audio-min=-100 audio-max=-20
/ interface wireless snooper
set multiple-channels=yes channel-time=200ms receive-errors=no
/ interface wireless sniffer
set multiple-channels=no channel-time=200ms only-headers=no receive-errors=no memory-limit=10 \
    file-name="" file-limit=10 streaming-enabled=no streaming-server=0.0.0.0 streaming-max-rate=0

I have experianced a simular issue as well but I was able to minimize it’s effects. It seems part of the problem with the ping going up and down is when your bandwidth is going up and down alot and quickly. If you watch your links you probibly see it go from 11 to 5.5 to 2 then 1 then back to 5.5 then back to 1. etc etc.. when the unit is making these bandwidth shifts you get a longer ping.

Try setting everyting at 1mb as a test and see if your ping evens out more. You will still see some spikes but it should be alot less than what your seeing now. I think the rest of the spike is some type of protocol overhead or something.

If at 1mb it lessens by alot or completly then look at an antani issue… pigtails, alignment, line of site, wind moving the antani’s.. etc etc.

-Michael

Michael,

What is interesting is situation, that this station was working perfectly on Planet WAP 1966. When I swithed to MT my problems started.

Antennas are quite near - max 1 km. They are correctley set up.
IMHO this is settings in MT problem. But don’t know what to set up :confused:

Thanks,
MJ

try leaving the basic-rate to 1Mb/s, set the tx-power to default, and change back the other settings that you might have changed (defaults work in most cases)

1Mb is not enough for me. Users has access to 4Mbit connection.

Why are you suggesting to set TX-power to default ? Is this has any influence to the performance ?

MJ

aha, so we see the reason of your problem. you are misinterpreting the meaning of this value. basic-rates means that it will work at any rate possible, starting from 1Mb. if you set it to a high value, and such speed is not possible, it will not work at all. SO - leave it to 1Mbit.

My mistake - sorry :wink:

I did something that in my opinion helped alot. I changed “data rate” speed from “auto” to “5.5”.
Also I have noticed, that preambule is set for “Both” (on MT side). And swithed it to logn.

Is there anything i can do to speed up this link ?

Also. I have problems with connectiong to AP (MT). Antenna is on the roof, it has 12DB and horizontal angle ~3deg. I’m one floor below. As you can see signal is quite strong, but pings… not.