Airport Express extremely slow over NAT/DHCP

Discussion in 'Mac Accessories' started by Fzang, Jan 1, 2015.

  1. Fzang macrumors 65816

    Fzang

    Joined:
    Jun 15, 2013
    #1
    I live in a dorm where using the internet requires one to log in. I have set up an Airport Express in my room and set it to DHCP/NAT which enables me to log in one and then use wifi freely on all my devices. However, this gives insanely slow wifi speeds.

    If I connect directly with bridge mode I get lightning fast internet, but then I can only use one device at a time, and I have to go through a lot of logging in/out troubles to use a different device.

    I have tried every possible configuration I could think of... Can anyone give me some pointers?
     
  2. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #2
    Does this issue only occur when running a Double NAT configuration?
     
  3. Fzang thread starter macrumors 65816

    Fzang

    Joined:
    Jun 15, 2013
    #3
    The router doesn't say anything about double NAT issues though. Not a problem then, is it?
     
  4. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #4
    When you have two routers in a single chain you have a double NAT issue. The speed issue is likely occurring as the upstream router is throttling your port. Another possibility is that running a double NAT firewall is causing the problem. Older AirPorts would let you use DHCP to distribute addresses without using the NAT function. I doubt that is still an option.
     
  5. Fzang thread starter macrumors 65816

    Fzang

    Joined:
    Jun 15, 2013
    #5
    It does have a DHCP-only mode. However, I was under the impression that NAT is absolutely required for one-IP-per-login systems commonly used in dorms and public hotspots?
     
  6. Altemose macrumors G3

    Altemose

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    Mar 26, 2013
    Location:
    Elkton, Maryland
    #6
    Not necessarily. DHCP would give one IP to the AirPort and create a separate DHCP range for clients connected to it. The DHCP option is under the "Network" tab correct?
     
  7. Fzang thread starter macrumors 65816

    Fzang

    Joined:
    Jun 15, 2013
    #7
    Correct.

    If I set router mode to DHCP-only and try to update, I get

    "Sharing a range of IP addresses using DHCP Only requires manually configuring your WAN IP address. If your ISP gives you a range of static IP addresses, you should manually configure your base station with the first IP address and distribute the rest via DHCP."

    So I should connect via "static" instead of DHCP? Which IP addresses should I use? With DHCP my IPv4 is set to 210.77.14.38; should I put this in static instead?
     
  8. Altemose macrumors G3

    Altemose

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    Mar 26, 2013
    Location:
    Elkton, Maryland
    #8
    Yes. Copy all of the information and input that in as static.
     
  9. Fzang thread starter macrumors 65816

    Fzang

    Joined:
    Jun 15, 2013
    #9
    I've tried several combinations now, and I'm finding that

    Static + bridge mode = good speed
    DHCP + bridge mode = good speed
    DHCP + NAT/DHCP = terrible speed
    Static + DHCP = no connection
    Static + NAT/DHCP = no connection

    Maybe I'm doing this wrong? :confused:
     
  10. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #10
    They are using an upstream router with a clear policy against routers as they "segment" the network. Your best option would be to manually log in on all devices or use the campus Wi-Fi if available.
     
  11. Fzang thread starter macrumors 65816

    Fzang

    Joined:
    Jun 15, 2013
    #11
    That's too bad. At least I found my problem :eek:

    I can only connect with one device at a time (hence the reason I wanted to use NAT) or it'll ask for login and kick off the previous device. But I guess fast internet for one device is better than unusably slow internet for several devices :D
     
  12. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #12

    Unfortunately you are at the mercy of the network engineers and administrators at your school. Though, if they do not want wireless routers or APs they should have a strong ubiquitous network.
     
  13. Fzang thread starter macrumors 65816

    Fzang

    Joined:
    Jun 15, 2013
    #13
    I study as a foreign student in China, and some things are just a bit slower here. Internet is one of them.
     
  14. Altemose macrumors G3

    Altemose

    Joined:
    Mar 26, 2013
    Location:
    Elkton, Maryland
    #14

    This is quite unfortunate.
     

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