Wireless again

As long-time readers of this blog will know, I have an extended wireless network. It now includes two daisy-chains and one spur: a daisy-chain on 802.11n (5GHz) with a TimeCapsule (which has internet connection from my ADSL modem/router) and two Extremes; a daisy-chain on 802.11g (2.5GHz) with older kit — two Extremes (one connected by ethernet to the remote end of the 802.11n chain) and three Expresses.

Autoconfigure was a welcome feature of the 802.11n Express. It was great — when it worked — but it was always flakey.

With the 7.4.1 firmware update my setup became completely unstable. In particular, whenever Time Machine started a backup the network would auto-reconfigure, and break. I had to use an ethernet connection direct to the Time Capsule to make a backup. I've now reverted to a manual setup of the WDS with explicit MAC numbers. All appears stable, my iPhone is back on WiFi and backup over wireless is working again.

If you're having problems with an autoconfigured wireless network, try going back to manually configured WDS. Use Airport Utility. First make a note of the Airport ID (MAC number) for each of your devices. Then, one-by-one switch from Create a Wireless Network or Extend a Wireless Network to Participate in a WDS Network. A WDS tab will appear. Under this tab you can see (and manually adjust) the autoconfigured setup. In my case I found that two Extremes were trying to act as WDS main.

As usual, be careful to update the various access points in an order that doesn't leave you unable to access some device over wireless. If you do get into that sorry state, a direct ethernet connection can be used to reconfigure the lost device.

Extreme 7.3.1 firmware update

All went smoothly, but now my remote base stations (I have a WDS daisy chain 4 links long - see earlier post) don't show in Airport Utility. Still connected - I can ping them just fine, and the remote airTunes express shows up in iTunes.

Update this seems to have been a temporary problem. Everything is now visible again.

All my airports (7 at last count) are configured in bridge mode - my speedtouch adsl modem router provides a DHCP server. On the bright side, this update seems to have helped with one issue: the 802.11n extremes now seem to pick up an IP address from my router using DHCP (previously I found this didn't work and had set manual IP addresses as a work-around).

802.11n

The following Macs have the 802.11n hardware built-in:

• * MacBook Pro with Intel Core 2 Duo
• * MacBook with Intel Core 2 Duo
• * Mac Pro with AirPort Extreme option
• * iMac with Intel Core 2 Duo (except the 17-inch, 1.83GHz iMac)

However, you will have to upgrade the firmware.

The CD that comes with your new airport extreme base station contains the AirPort Extreme 802.11n enabler, which updates the firmware on your airport card to enable 802.11n high-speed WiFi:

• 74 - 248 Mbit/s
• 70 - 160 metres range

If you buy a third-party 802.11n base station, you can get the enabler from the Apple store for $1.99

Airport Extreme WDS daisy chain

I've added two airport extreme 802.11n base stations to my WDS network. Mostly this was straightforward. The basic procedure is just as described earlier for the previous Airport models. The UI of the new Airport Utility app is clearer than the previous version.

However, I found the two Airport Extreme base stations got confused when I used DHCP to link them into the network. Instead, I've given them manually assigned IP addresses - in the same 10.0.0.xxx range as I use for DHCP. My Alcatel Speedtouch DSL modem acts as a DHCP server, and I've set it to distribute addresses above 10.0.0.16 — which leaves me plenty of addresses below this to allocate manually.

The network is now something like this (with some base stations running the full range of protocols, 802.11b,g,n, and othersonly one of these, as shown):

     airport(b)  express(g) = speakers
            \    /
    disk = extreme(b,g,n) - airport(g) - express(g)
           /                                 \         
       = extreme(b,g,n) = printer          express(g) = speakers
      |       
router     
      |
       = airport(b,g)

Here, "airport" means an old conical airport extreme; express is the small block airtunes gizmo; extreme is the new 802.11n-capable mini-sized device.

To insert a new base station into my existing network, I first set its MAC address (aka airport ID) as the WDS main value for each of its children; then I configured the new base station with the children's MAC addresses in the WDS remotes list.

To configure the new devices I found it easiest to switch off the other base stations, and connect wirelessly to the new device. If you click on the name of a setting shown under the Summary tab, you are taken directly to the tab where you can edit the value. You want Wireless Mode: Participate in a WDS network. You should also set the Channel: and Network Name: to match the other base stations. Then you can set IP Address:. (As described above, DHCP confuses my two new Express base stations, so I set Configure IPv4: Manually. You can find the subnet mask and router address from the configuration of another base station. You may want to try Configure IPv4: Use DHCP first, as this is simpler.) For WDS relay and remotes you want Connection Sharing: Off (Bridge Mode). This is also correct for the WDS root if your modem acts as a DHCP server; otherwise you may need the WDS root to act as DHCP server (Distribute a range of IP addresses).