7 Replies Latest reply: Jun 29, 2010 9:15 AM by bkelly0123
bkelly0123 Level 1 Level 1 (0 points)
I have a few questions about the best way to extend my wireless network throughout the house and onto the patio. I have a wired Ethernet network throughout the house. The main AEBS (simultaneous dual-band) is providing DHCP for the whole network.

A second simultaneous dual-band AEBS is located on the other end of the house, configured to "extend a wireless network" AND wired into the Ethernet network. This seems to be working well, but I want to understand a few things:

1. Am I losing bandwidth by extending the wireless network, or does that issue only apply when connecting only wirelessly (NOT using an Ethernet connection between the two AEBS units)?

2. Can I "extend a wireless network" to a third AEBS unit in another part of the house (near the patio for better wifi outside)? What is the limit on the number of wireless devices I can use to extend the wireless network -- assuming all are networked via Ethernet?

3. Am I extending both the B/G and N bands (since I am using two AEBS simultaneous dual-band units)?

Thanks for any advice / education on these concepts!!

iMac 9.1, Mac OS X (10.6.4)
  • Tesserax Level 8 Level 8 (49,415 points)
    Hello bkelly0123. Welcome to the Apple Discussions!

    1. Am I losing bandwidth by extending the wireless network, or does that issue only apply when connecting only wirelessly (NOT using an Ethernet connection between the two AEBS units)?


    Yes. Bandwidth loss is common when extending the AirPort with another by wireless. Since you already have them connected to an Ethernet backbone, you want to configure them for a "roaming" network and not for a Wireless Distribution System (WDS).

    2. Can I "extend a wireless network" to a third AEBS unit in another part of the house (near the patio for better wifi outside)?


    Yes, but not with the newer dynamic WDS. Instead, you would need to configure the three base stations into the older static WDS configuration. This type of WDS supported three types of base station configurations: main, relay, & remote. It also only operates in the 802.11g mode with significant bandwidth penalties.

    What is the limit on the number of wireless devices I can use to extend the wireless network -- assuming all are networked via Ethernet?


    Basically, an unlimited amount. However, is relative tight quarters you would need to take into consideration of the radio channel that each base station would operate on as to not conflict with the next one closest to it.

    3. Am I extending both the B/G and N bands (since I am using two AEBS simultaneous dual-band units)?


    You would be extending both the 2.4 GHz & 5 GHz radios. Note: 802.11n can operate on either radio; while 802.11b/g can only operate on the 2.4 GHz band.

    Again, since you already have an Ethernet backbone, you will NOT want to use a WDS. Instead, you will want to configure your AirPorts for a "roaming" network. In this type of network, you can literally "roam" with a laptop from room to room and still be on the "same" wireless network.

    The following is the basic steps to configure a "roaming" network:

    To setup an 802.11n AirPort Extreme Base Station (AEBSn) as a roaming network:
    Network configuration: DSL/Cable Modem or Internet Router > (Ethernet cable) > [WAN] AEBSn#1 [LAN] > (Ethernet cable) > [LAN] AEBSn#2 [LAN] > (Ethernet cable) > [LAN] AEBSn#N

    Setup the AEBSn connected to the Internet to "Share a public IP address."
    Internet > Internet Connection > Connection Sharing: Share a public IP address

    Setup the remaining AEBSn(s), as a bridge.
    Internet > Internet Connection > Connection Sharing: Off (Bridge Mode)

    For each AEBSn in the roaming network:
    o Connect to the same subnet of the Ethernet network
    o Provide a unique Base Station Name
    o The Network Name should be identical
    o If using security, use the same encryption type (WEP, WPA, etc.) and password.
    o Make sure that the channel is set at least three channels apart from the next AEBSn.
  • bkelly0123 Level 1 Level 1 (0 points)
    Wow! Thanks for the very comprehensive reply. I appreciate the help!

    I still have a few basic questions. I used the AirPort Utility's "Extend a wireless network" functionality to do this, and I think that AirPort Utility accomplished all the steps you suggested EXCEPT for providing different radio channels. Please see below and advise whether I'm OK this way.

    The following is the basic steps to configure a "roaming" network:

    To setup an 802.11n AirPort Extreme Base Station (AEBSn) as a roaming network:
    Network configuration: DSL/Cable Modem or Internet Router > (Ethernet cable) > [WAN] AEBSn#1 [LAN] > (Ethernet cable) > [LAN] AEBSn#2 [LAN] > (Ethernet cable) > [LAN] AEBSn#N


    This is how I'm configured. There's an unmanaged switch in the mix, but same idea.


    Setup the AEBSn connected to the Internet to "Share a public IP address."
    Internet > Internet Connection > Connection Sharing: Share a public IP address


    This was configured automatically this way by AirPort Utility (and grayed out) when I set this AEBSn to "Create a wireless network" and selected "Allow this network to be extended" on the first AEBSn.

    Setup the remaining AEBSn(s), as a bridge.
    Internet > Internet Connection > Connection Sharing: Off (Bridge Mode)


    This was also configured automatically this way by AirPort Utility (and grayed out) when I selected "Extend a wireless network" and checked "Allow wireless clients" on the second AEBSn.

    For each AEBSn in the roaming network:
    o Connect to the same subnet of the Ethernet network


    Yes

    o Provide a unique Base Station Name


    Yes

    o The Network Name should be identical


    Yes, because AirPort Utility provided the dropdown list to choose the Wireless Network Name to be extended.

    o If using security, use the same encryption type (WEP, WPA, etc.) and password.


    Yes.

    o Make sure that the channel is set at least three channels apart from the next AEBSn.


    This is one that did NOT occur automatically and appears to be impossible to set. When I select the wireless mode as "Extend a wireless network" on the second AEBSn, the option relating to channel selection (automatic or manual) is not available in AirPort Utility for the second AEBSn. I am using AirPort Utility 5.5.1.

    I have the first AEBSn set to "Automatic" channel selection, which happens to choose channels 149 and 11 at the moment. My nearest neighbors are both on channel 6, so this seems to work fine.

    As an experiment, I tried setting the first AEBSn to manual channel selection. When I do this, I cannot even see the second AEBSn in AirPort Utility, and it is stuck on a flashing yellow light. When I switch the first AEBSn back to "automatic" channel selection, the second AEBSn then reappears in AirPort utility and selects the same channels as the first AEBSn.

    So it sure seems that the intent of Apple in AirPort Utility is for the "Extend a wireless network" function to use automatic channel selection and to sync the channels on the extended AEBSn.

    I assumed that having both AEBSn units on the same channels made the broadcast on these channels extra strong, but I guess a device has to connect to one individual AEBSn, so broadcasting on the same channel effectively creates competition on that channel? Is that the right way to think about it?

    If I broadcast on different channels, will I have situations where a device "locks on" to the AEBSn with the weaker signal, even though another AEBSn is closer and would provide a stronger signal? Or do wireless devices continually poll for the stronger signal on the wireless network?

    Thanks again for the awesome reply to my first post!!
  • Tesserax Level 8 Level 8 (49,415 points)
    I still have a few basic questions. I used the AirPort Utility's "Extend a wireless network" functionality to do this, and I think that AirPort Utility accomplished all the steps you suggested EXCEPT for providing different radio channels. Please see below and advise whether I'm OK this way.


    It is important to understand that when attempting to extend one AirPort with another, AND they are to be connected wirelessly, is the only time that you would use the "Extend a wireless network" and "Allow this network to be extended" options in the AirPort Utility. These are not required and are actually undesirable when the AirPorts will be connected by Ethernet.

    In a "roaming" network configuration, the "main" base station is connected to the Internet modem and is configured to both "Share a public IP address" and "Create a wireless network." All other base stations need to be connected back to this main base station by Ethernet. In addition, each of these other base stations would need to be configured to both "Create a wireless network" and with "Connection Sharing = Off (Bridge Mode)" as they will be performing like Wireless Access Points.

    You can find some additional information about configuring a "roaming" network on pages 40 & 41 of the Designing AirPort Networks Using AirPort Utility Mac OS X v10.5 + Windows document from Apple Support.
  • Bob Timmons Level 10 Level 10 (89,720 points)
    +This was configured automatically this way by AirPort Utility (and grayed out) when I set this AEBSn to "Create a wireless network" and selected "Allow this network to be extended" on the first AEBSn.+

    You don't need to check the "Allow this network to be extended box". That is used if you are extending using wireless only and it appears that you are using ethernet.

    +This was also configured automatically this way by AirPort Utility (and grayed out) when I selected "Extend a wireless network" and checked "Allow wireless clients" on the second AEBSn.+

    "Extend a wireless network" is only used if you are extending using wireless only. Since you are extending using ethernet, the correct setting for this device and any other "remote" connected by ethernet would be "Create a wireless network". Yes, this is confusing, but "Create" is the correct setting when you extend using an ethernet backbone.
  • bkelly0123 Level 1 Level 1 (0 points)
    As I've thought about this and done some more searching, I think your first answer implied that both AEBSn units should be set to "Create a wireless network" and then manually configured from there as documented.

    In this way, both AEBSn units could be configured to operate on different channels.

    If that understanding is correct, what happens when the AEBSn units are both set to "automatic" channels? Do they automatically seek out different channels to avoid conflict?

    Also, why does the "Extend a wireless network" function choose to place all AirPort units on the same channels if this is not the most effective way to extend the network?

    Thanks!
  • Bob Timmons Level 10 Level 10 (89,720 points)
    I think you meant to say that Tesserax's first answer implied....but, yes, I think that is what Tesserax intended to say as that is the correct method.

    If both AEBS units are set to Automatic channel settings, this will almost always work fine, as the AEBS will "automatically" look for the proper channels to use. If you want to set the channels manually, set them at least 4-5 channels apart to minimize the chances of interference. The problem with setting channels manually is that there might already be other networks using those channels and your connection speed may suffer. Automatic will, in theory, choose the best channel for each device "automatically".

    +Also, why does the "Extend a wireless network" function choose to place all AirPort units on the same channels if this is not the most effective way to extend the network?+

    It is the most effective (and only) way to extend the network when you are using wireless only to communicate between devices.

    When you extend using an ethernet backbone, you are technically creating different networks, but they have the same wireless network name to allow devices to "roam" and pick up the best available signal. If you assigned different network names instead of using the same name, you would have different networks, in which each would require a separate log on.

    Message was edited by: Bob Timmons
  • bkelly0123 Level 1 Level 1 (0 points)
    Bob and Tesserax:

    Thank you both!! You guys are awesome!

    I actually now have a better understanding of networking (wired and wireless) and will implement these changes tonight when I get home.

    I plan to try automatic channel selection on all AEBSn units and will see how that goes.

    I also ordered another Airport Extreme and will soon have three AEBSn units in the house. I'm very hopeful I'll now get a strong signal everywhere, including the patio, for our many wireless devices (iPhone, iPad, netbook, laptops, etc.).

    Thanks for the very quick and thorough replies!!!