7 Replies Latest reply: May 28, 2012 10:49 AM by Courcoul
Sindox Level 1 Level 1 (0 points)

I know that WIFI is supposed to be 40% slower than ethernet, but I'm having some troubles with the speed on my Macbook Pro and iPad over wifi.


I tested the speed on ethernet and this is my real speed




But instead on WIFI I'm getting this




It seems it's only affecting download speed I don't know what to do, what may be causing this problem? my router is a belkin N150

MacBook Pro (13-inch Mid 2010), Mac OS X (10.7.3)
  • 1. Re: Wifi speed is WAY slower than ethernet
    ds store Level 7 Level 7 (30,305 points)

    Your WiFI download speed should be about 20 mp/s, you do have a serious issue.



    My advice is:


    1: update your routers firmware


    2: run a wifi sniffer to find out what channels other routers are on in the area and set yours way from theirs


    3: follow the advice here and change all your passwords etc.


    WiFi, Internet problems, possible solutions


    WiFi security issues, at home and WiFi hotspots


    4: if the router is still slow, consider replacing it, move closer to the router

  • 2. Re: Wifi speed is WAY slower than ethernet
    Network 23 Level 6 Level 6 (11,690 points)

    Also do a survey of your area for sources of interference:


  • 3. Re: Wifi speed is WAY slower than ethernet
    Sindox Level 1 Level 1 (0 points)

    Thanks for all your advice, I tried everything you said and at the end the problem had something to do with an option called "QoS" if you have that on in you router turn it off

  • 4. Re: Wifi speed is WAY slower than ethernet
    Network 23 Level 6 Level 6 (11,690 points)

    Interesting that you found it to be the cause on your router. I just checked and on mine, QoS is on for both IPv4 and IPv6, and I get 100% of my ISP's speed, so it might not always be the cause. Sounds like it might depend on the type of router someone is using.


    But if turning it off works in your case, that's good to hear.

  • 5. Re: Wifi speed is WAY slower than ethernet
    Thomas Brierley Level 3 Level 3 (540 points)

    Actually you should get the same bandwidth but higher latency... speedtest.net only test your internet connection.


    ethernet = 1000 or 100 Mbits


    Wifi (802.11g) = 54Mbits max


    Your internet connection is much slower than ether of those, the difference with wifi however is that you can get interferance like the other posters here are suggesting. whichever is the common denominator is what speedtest will measure. in the case of ethernet it's showing your true internet connection throughput. in the case of WiFi it's showing your current wifi speed.


    Just wanted to clarify.


    So yeah... you need to see what channels other people are using. and use the most distant channel (consider that wifi channels over lap each other, i.e. 6 overlaps 7 and 5).


    you might also want to try switching between g and n mode, as each uses different spectrums which will have different levels of interfearance depending on usage and location... you dont need the full bandwidth of n if you internet connection is only 20Mbits... becase g is twice that anyway.

  • 6. Re: Wifi speed is WAY slower than ethernet
    andrewv02 Level 1 Level 1 (0 points)

    Hello Sindox,


    I also had the same problem. Initally my speed was 3.8Mbps. I have a Macbook Pro running Mac OSX 10.6.8. My router is a Dlink  DIR-655 with QoS. I turned off the QoS and my speeds returned. I ran Speedtest.net and recieved 15.8Mbps. That is what I was suppose to get. Then I went back into my router and turned QoS back on and rebooted the router. I performed another speedtest and I recieved similar results 16.5Mbps.  So you were correct in the QoS causing the problem. But why it was happending I don't know must be some sort of conflict with the QoS processing. One last piece of info this started to happen after I changed my DNS to OpenDNS. Not saying that was the cause but it could have been. Now everything is working perfectly. Maybe someone else out there had the same issue. Goodluck!

  • 7. Re: Wifi speed is WAY slower than ethernet
    Courcoul Level 6 Level 6 (11,470 points)

    Since IPv6 was mentioned, if your ISP is not using/deploying it right now, consider disabling it on the Mac. Many routers freak out when a device starts hammering them for its global prefix. My 2Wire napkin holder wouldn't let me download a single patch from Apple till I shut IPv6 down for now.


    Yes, we will all have to go live in the happy world of ginormeous IP addresses, but deployment has been dragging its feet since the start of the century.  /___sbsstatic___/migration-images/185/18501961-1.gif