8 Replies Latest reply: Mar 4, 2008 6:12 AM by treaders
Kurt Marek Level 1 (20 points)
I just got ATT UVerse installed and I had to do all sorts of crazy stuff (to me anyway) to get it to work and I'd like some help in understanding what it all means.

I used to have my cable modem plugged into my Airport Extreme which served IP addresses via DHCP to my computers and my Airport Express (working just for iTunes).

I now have my Airport Extreme connected to the residential gateway and in DMZ mode. What is this and is it secure?

I can no longer assign IPs to my computers using DHCP from my Airport Extreme. I had to set it to Bridge mode and the computers now seem to get IPs from the residential gateway (?).

Everything seems to work, including my iTunes to my living room Airport Express, but I am concerned because I don't really understand how all this is working. This gives my security stress. It all made sense to me when I just had my cable modem plugged into my Airport Extreme and it created a closed wireless network with a good password and only allowed my computers/iPhone's MAC addresses to connect and assigned the IP addresses.

Can someone explain to me how this DMZ and Bridge mode works and what I should look for and configure to get things secure again?

iMac 24, iMac 20, PowerBook G4, Mac OS X (10.5)
  • Henry B. Level 9 (78,690 points)
    The "DMZ" feature is not relevant to a Base Station in bridge mode - it only operates when the Base Station is functioning as a router.

    You basically answered your own question. Your Base Station is in bridge mode (its router is disabled). your network devices get their IP addresses from your "residential gateway". The "residential gateway" is in fact a combo modem/router. So indeed your network is secure, because everything is behind the router built into your "residential gateway".
  • Kurt Marek Level 1 (20 points)
    Thanks for the response. I guess the way I want it setup is to have my Airport act as the router. I thought putting it in the DMZ would accomplish this, but if I leave the Airport assigning DHCP addresses to my computers, I lose access to the internet.

    My reasoning is that I will be upgrading to 802.11n when I get my AppleTV. I don't want my network crippled by the slower residential gateway.

    Maybe I'm thinking about this incorrectly.

  • Henry B. Level 9 (78,690 points)
    I suggest you leave things as they are. It is just as secure, and just as fast, as if the Base Station was providing the routing for your network. The router built into the residential gateway can function at a speed far in excess of its broadband connection to the internet.

    When you upgrade to 802.11n, just configure that base station exactly the same way (ie base station in bridge mode). As long as everything in your network is connected to the base station (wired or wireless) then communication between devices on your own LAN will function at the maximum speed of the base station's own gigabit switch and wireless network.
  • treaders Level 1 (5 points)

    Would you mind explaining how you set up your Airport Extreme behind the U-Verse Residential Gateway?

    The reason I ask is that I'm having problems maintaining a constant wireless U-verse internet connection using both my MacBook and iMac computers to the RG. However, my PC notebook maintains a steady wireless internet connection to the RG. I have the Max internet connection from U-verse.

    The Airport icon in the top right hand side of the MacBook screen disappears for 30-60 seconds before restoring the U-verse connection. This problems occurs on both the MacBook and iMac. It occurs every 30 minutes or so.

    I did try installing my Airport Express behind the U-verse RG but I had the same problem with the internet dropping out. When I connected the Airport Express behind the RG I did not change any settings on the RG screen at IP and I think this is where I have made a mistake.

    I currently resolve the problem either by waiting 30-60 seconds or I click the Airport icon in the top right hand side of the screen, choose the U-verse wireless connection from the drop-down list (the U-verse wireless service appears each time in the list) and then the internet connection is restored.

    Very strange given that the PC notebook does not encounter any problems. I even installed a small wireless signal strength application on the PC to check that the wireless is not dropping out. I have not noticed it drop out yet.

  • Gully Level 1 (100 points)
    Ben...did you figure that out?

    I have the same problem with my MacBook only. My MacBook Pro and iMac never lose signal...only the MacBook.

    Can't figure if it's an RG issue or the Air Port card...anyone have a POV?
  • Mason828 Level 1 (0 points)

    I “may” have found the solution. The issue for me was that the wireless AT&T Uverse connection for my Macbook running Leopard 10.5.2 was dropping the connection. Very unstable.

    This is all I did.

    First go to this link and install this widget:


    Next, quickly read this article:


    The key information found in the article is that channels 1, 6 and 11 are the best channels.

    I made sure that no networks were working in my area on channel 1, using the widget installed from the link above.

    I went into my Uverse Router and I changed the channel setting from “automatic” to channel 1.

    I saved it.

    At BEST I would occasionally get 45 straight minutes of internet connectivity. After 3 days of testing my issue is solved.

    Now, while some might say that the solution should have been obvious that I needed to make sure I didn’t have interference, using just the Widget as my guide, I can tell you based solely on this information that I didn’t have any strong signals coming from any neighbors that conflicted with the channel I had. I believe that the significant change came from changing the router from auto connection to a fixed channel selection, in my case channel 1.
  • weirdbeardmt Level 1 (5 points)
    I have the same problem. Wireless was working absolutely fine on the previous Linksys router but since having the U-verse installation I've been getting the random (well semi-random, it's seems to be every 10 minutes or so) dropouts.

    I have changed the SSID of the router to something other than 10 and will report back what happens.
  • treaders Level 1 (5 points)
    My solution was to connect my existing Airport Express (AE) router to the U-verse Residential Gateway (RG). I went into the RG settings and put the AE into the DMZ zone (which I believe stands for de-militarized zone or similar). This makes the RG think the AE is in front of the RG and therefore the RG does not put any firewall settings on to the AE.

    It seems to work ok now. Never had any problems with my laptop PC and the RG, only my MacBook and the RG.