Network Question

Discussion in 'Mac Basics and Help' started by brentg33, Jul 31, 2012.

  1. brentg33 macrumors 6502a

    Mar 5, 2007
    Hi all,
    I use Comcast for my ISP. I have a Docsis 3.0 modem and an older Airport Extreme. Pre-gigabit ethernet, i believe this was fast-ethernet 100T. Anyways. i also have an older linksys G router running dd-wrt in bridge mode. The idea was to have the airport at 5ghz N and the linksys at 2.4ghz G. (my APE is not dual band i believe). Ok so that is my set up. So today i receive an email from Comcast, they are doubling my speed, just need to power-cycle my modem. try a few times and no look. Running speed test on my mid 2011 iMac (connected via 5ghz N) and I'm still stuck at 25mbps down (should now be 50). call comcast...they reset my modem, now i can get about 35mbps down....closer...but not quite 50. meanwhile i am now getting the new double speed increase of 10mbps up. Comcast and myself can not figure out why i can get my full 50mbps down. So just now, i decide to ethernet from the APE to my iMac....and magically....50mbps down.....just like that.....
    so my long, drawn out question....why cant i get 50mbps down via 5ghz N on my APE wifi? is this some limitation of the older APE?

    thanks in advance....
  2. miles01110 macrumors Core


    Jul 24, 2006
    The Ivory Tower (I'm not coming down)
    Because you never get the full advertised speed over a wireless network?
  3. brentg33 thread starter macrumors 6502a

    Mar 5, 2007
    ok, i understand that. its just that i still though it should be closer than 35mbps vs 50mbps....espeically over 5ghz N. the APE sits inches anyway from the iMac as it is.
  4. BrianBaughn macrumors 603


    Feb 13, 2011
    Baltimore, Maryland
    Have you looked up the maximum theoretical speed for a 5GHZ wifi connection?
  5. DaveGillam, Aug 1, 2012
    Last edited: Aug 1, 2012

    DaveGillam macrumors newbie

    Aug 1, 2012
    Cable Modems & Competing Wifi

    A couple of details:

    1) Cable modem services are usually shared-bandwidth models, so your speed is determined by how many other people on your segment are also using the service. When I was on such a service, I paid for 15Mbps, but never saw more than 10Mbps, due to all the other people in the neighborhood using the same service. That's a 33% drop in top advertised speed. Getting 35Mbps in a 50Mbps setting is a similar 30% drop.

    2) If you have both an N and a G wifi on the same network, the N router may be downgrading itself automatically to G speeds, in order to stay compatible. My advice is to upgrade your routers to newer models that can do both N and G simultaneously without needing to downgrade speed to the common G range.


    Gillam Data Services

Share This Page