snowfish

Q: 5GHz 802.11ac Network

By default, does an AirPort Extreme or an AirPort Time Capsule provide both 2.4GHz and 5GHz connections? Or does it take some steps to set up a 5GHz network? Is it done by choosing "wireless options" in AirPort Utility and ticking the box opposite "5GHz network name"? Thank you.

MacBook Pro with Retina display, OS X El Capitan (10.11.1)

Posted on Nov 12, 2015 10:25 PM

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Q: 5GHz 802.11ac Network

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  • by UGADog,

    UGADog UGADog Nov 12, 2015 10:34 PM in response to snowfish
    Level 4 (1,902 points)
    Mac OS X
    Nov 12, 2015 10:34 PM in response to snowfish

    The TC and Extreme operates in both modes simultaneously when in default mode.  They use their firmware logic to determine when each is the better choice at a given time.  Sometimes it makes mistakes and people opt to force a 5GHz network by checking the  5 GHz network option in set up.  Mine (TC and Express) work fine in auto-mode.

  • by snowfish,

    snowfish snowfish Nov 12, 2015 10:44 PM in response to UGADog
    Level 1 (0 points)
    Nov 12, 2015 10:44 PM in response to UGADog

    I asked because I ran Wireless Diagnostics and the result says that my channel is crowded with neighbouring networks and it suggests I create a 5GHz network. Should I tick the box and name a 5GHz network then?

  • by UGADog,

    UGADog UGADog Nov 12, 2015 10:53 PM in response to snowfish
    Level 4 (1,902 points)
    Mac OS X
    Nov 12, 2015 10:53 PM in response to snowfish

    Yes, I would do it and see if the network performs well.  The only downside is that 5 GHz does not travel as far or through walls and ceilings as well as 204 GHz.  This may not be a problem for you or the noise in the 2.4 GHz could be so bad that a weak 5 GHz signal is still better.  5 GHz is also much faster than 2.4 GHz when not on the edge of its service area.  Test and find out what you think.  It is simple to turn off later.

  • by Csound1,

    Csound1 Csound1 Nov 12, 2015 11:08 PM in response to UGADog
    Level 9 (50,861 points)
    Desktops
    Nov 12, 2015 11:08 PM in response to UGADog

    There is no speed difference between different frequencies, the same protocols run on both. Wireless G, or N etc is the same at any frequency.

  • by UGADog,

    UGADog UGADog Nov 12, 2015 11:22 PM in response to Csound1
    Level 4 (1,902 points)
    Mac OS X
    Nov 12, 2015 11:22 PM in response to Csound1

    802.11 ac is never 2.4 GHz.  802.11g is never 5 GHz. ac is of course much faster than g.  How is what you say true then? This is why they are dual band routers - for the fastest connection at a particular distance and obstacle.  802.11n works both 2.4 GHz and 5 GHz but 5 GHz is capable of speeds twice as fast as 2.4 GHz n 

  • by snowfish,

    snowfish snowfish Nov 12, 2015 11:38 PM in response to UGADog
    Level 1 (0 points)
    Nov 12, 2015 11:38 PM in response to UGADog

    This post is duplicated as a result of system error.

  • by snowfish,

    snowfish snowfish Nov 12, 2015 11:36 PM in response to UGADog
    Level 1 (0 points)
    Nov 12, 2015 11:36 PM in response to UGADog

    5GHz performance is somewhat better. But after clicking the 5GHz box and naming a 5GHz network in "wireless options", does it mean that there are no longer any 2.4GHz signals? My ageing mother uses a couple of older devices which are not 802.11ac. Will her older devices, which might be 802.11g or 802.11n, still be able to connect to the updated WiFi network here?

     

    One more thing. Should DNS Servers be entered in "Network" in "System Preferences" instead of both or either of the AirPort Time Capsule and AirPort Extreme which make up my network?

  • by Csound1,

    Csound1 Csound1 Nov 13, 2015 5:39 AM in response to UGADog
    Level 9 (50,861 points)
    Desktops
    Nov 13, 2015 5:39 AM in response to UGADog

    UGADog wrote:

     

    802.11 ac is never 2.4 GHz.  802.11g is never 5 GHz. ac is of course much faster than g.  How is what you say true then? This is why they are dual band routers - for the fastest connection at a particular distance and obstacle.  802.11n works both 2.4 GHz and 5 GHz but 5 GHz is capable of speeds twice as fast as 2.4 GHz n

    I can only say that you should believe whatever you want, regardless of it's veracity.

  • by UGADog,Solvedanswer

    UGADog UGADog Nov 13, 2015 9:07 PM in response to snowfish
    Level 4 (1,902 points)
    Mac OS X
    Nov 13, 2015 9:07 PM in response to snowfish

    But after clicking the 5GHz box and naming a 5GHz network in "wireless options", does it mean that there are no longer any 2.4GHz signals? My ageing mother uses a couple of older devices which are not 802.11ac. Will her older devices, which might be 802.11g or 802.11n, still be able to connect to the updated WiFi network here?

     

    The TC and Extreme will still create a 2.4 GHz network with the name specified in the Wireless Network Name field.  So you are setting up two networks at once (three actually if you set up a Guest network too) and both have to be connected to individually.  So your mother might connect to the 2.4 GHz network for her computing and it be used for devices like HP printers which at last check were all 2.4 GHz (though that can be overcome with a USB cable connection to a 5 GHz device).  Obviously the switching between the two can become a pain it both 2.4 GHz and 5 GHz are used routinely with different devices and each network.  And the devices need to be on the save network to communicate with each other, which is why I leave my network on  automatic.  But I do have less noise and don't get the diagnostic advice you get.

     

    You might be able to find a "quieter" 2.4 GHz channel by listening for an extended period and studying the logs.  Apple's tool is explained here but other tools are more convenient to read to me.  I've used WiFi Scanner most recently but there are lots of similar tools to choose from. You can then manually select a channel for 2.4 GHz under the TC or Extreme Wireless > Wireless Options in AirPort Utility for the quietest channel over time, and let the TC and Extreme switch to 5 GHz on one network when it thinks best without creating a separate 5 GHz network outright.

     

    Should DNS Servers be entered in "Network" in "System Preferences" instead of both or either of the AirPort Time Capsule and AirPort Extreme which make up my network?

     

    DNS Servers should be changed on the Modem whenever possible.  If you change it there you don't need to worry about a change on TC or Extreme.  And if you can't change on modem (some ISP prevent this) you can change on the primary wifi device (the one creating the network) if you have the other device set to extend network.  This is also true if you have the devices connected by ethernet to create a Roaming Network.  Primary device connected to WAN as close as you can get to the WAN is best place to change DNS.  I know of no reason to set DNS independently on each device though I sure there are cases when people find it useful.