HDTV over WiFi: 802.11a helps

No, we're never satisfied. You'd think that just having the ability to stream HDTV over WiFi would be good enough, but it's not. We want it to be flawless; no hiccups, stutters, pixelation, nothing. Since we don't have a hard-wired Ethernet solution, nor a screaming Ethernet over Coax option just yet, we took the plunge and snapped up another router: the Linksys WRT55AG.

While the picture above may look like a funky blue insect, it's actually our new 802.11a router sitting on top of our 802.11g router. The longer antennas are the high gain range extenders that didn't really help our HDTV, but now we can sit in our neighbor's bathroom and surf the web on Sunday mornings. Find out after the jump how we set this configuration up and if it helped bring HDTV perfection to our Xbox 360.

Basically, we now have two wireless networks in the house. The 802.11g router is used for the work laptops and has specific SSID and WEP requirements. That router is set up a little more securely, so we plugged our broadband into that router directly. We keep that router in mixed mode for both "b" and "g" clients since we have both types of WiFi clients.

We're letting the 802.11a router be totally unfettered by security, for two reasons. First of all, that slows things up and the point here is to speed them up. Secondly, the router is still protected by NAT as it will sit behind the first router. Yes, if you sit in front of our house, you might be able to wirelessly surf the web, but since you don't know where we live, we feel pretty safe! This router is protected from outside Web intrusion, so we're comfortable to at least test this configuration out.

To have the 802.11a router sit behind the 802.11g router in our network topology, we simply plug some Cat-5 wire out of the g router and into the "Internet" jack of the "a" router. Essentially, all Internet traffic from "a" passes through "g" and vice-versa. The new router is actually capable of supporting a, b, and g clients, however we disabled the g radio as shown below. There shouldn't be any interferance because these radios are on completely different frequencies, but why keep the radio on if it won't be used?

One additional important point. Both routers can't have the same IP address. By default both of these Linksys routers want the private IP of 192.168.1.1. Once you set up the second router, be sure to modify the IP address so that it's on a different network.

Next up is to make sure your Xbox 360 can see the new network. In the Network Settings of the 360 Dashboard, you should now see your new network under whatever name you gave it. If you grab the Linksys router that we did, the default SSID or network name is "linksys-a". For security reasons, we definitely recommend changing that. Find your new network on the 360, test the connections and you should be all set!

One little "gotcha" that might only apply to this model router: there is a Turbo mode setting on it. We tried to use it, but the 360 didn't see the network, so we turned it off. Choosing an auto mode or a 54 Mbps transfer mode seemed to work the best. This confirms that the 360 is unlikely to natively work with any of the pre-N or SpeedBoost routers on the market that claim 108 Mbps or more. That makes sense, since the Microsoft adapter isn't capable of anything higher than 54 Mbps.

So, after dropping the extra dough and configuring the new network, how did it work? The graph below shows that we're above the minimum line for HDTV transmission from the Windows Media Center PC to the Xbox 360 for the entire test we ran.

Not only are we above the line, but we're stable when you compare the chart to our test on the 802.11g router. This is likely due to the different radio frequency; there's less interference form microwave ovens, cordless phones and other WiFi networks.

Aside from the technical proof that the new router is a much better choice, the actual practice of using the new network is much more enjoyable. We've watched several hours of HDTV on our home brewed Windows Media Center over WiFi on the Xbox 360. Even when the cats decide to wrestle next to the Xbox, we haven't seen any impact on the signal. Of course, the cats tend to have our full attention when they decide to play "WWF", so we might have missed a stutter on our set!