DIY, HDTV over WiFi: tips and tricks
By Kevin C. Tofel 
posted Dec 15th 2005 10:32AM
posted Dec 15th 2005 10:32AM
Well, that graph says it all, doesn't it? This is the Windows Media Center Network Performance Tuner in action and it could spell doom for HDTV over WiFi. Let me explain a little. We showed you a video where we streamed high-def content from a Media Center PC to an Xbox 360 via WiFi. Luckily it all worked out, but there's some things you need to know if you plan to go this route.
If you recall, we were demonstrating the Windows Media Extender technology with the Xbox 360 for high-def. I'll say right up front, it works as advertised: you can stream high-definition content to the 360 that's hooked up to an HDTV set. I've been completely impressed with the quality of the streaming; both recorded HD as well as live. The best way to say it: there is no noticeable difference if I'm watching HD via my over-the-air tuner or from the Xbox 360.
So what's the kicker? Bandwidth, baby...bandwidth. Those MPEG-2 streams I used to watch OTA can be up to 19.39 megabits-per-second. If you don't have the pipe for that bandwidth, your video will be choppy, will stutter, or will even be dropped for a time.
"OK," you say, "so for me to do this via WiFi, I need to have fast WiFi capability." You guessed it, but your options are VERY limited if you want to use the Xbox 360 for one reason and one reason only. The WiFi adapter for the unit is capable of the three main 802.11x standards: a, b, and g. Don't even consider the 802.11b network for this purpose. It's fine for Xbox Live, but the 11 Mbps speed won't even come close for high-def streaming.
This gives you the 802.11a or 802.11g choices, both of which are advertised at up to 54 Mbps. Sounds plenty fast enough, right? On paper, yes; in practice, not necessarily as evidenced by the graph below. For example: I'm using an 802.11g router in my office. My office is on the second floor of my home and the Xbox 360 is in the room directly below the office. The direct distance between the router and the 360 is roughly 15 feet and there are no metal vents or anything else in the floor between the two. I also have the Linksys Range Extender antennas on the router that boost the signal 7 dbs.
You can see that until I positioned the router antennas "just right" I didn't have a signal stable enough for high-def streaming. Even when I did, I'm cutting it really close as evidenced by hours of actual testing. All it takes is for one of our cats to walk past the 360 and we get a stutter or two (on the video, not on the cats!)
So, what can you do? Well, Microsoft does provide a website that makes some suggestions, but most of these were common sense to me. "Don't hide your router behind a plant" should be a standard rule for WiFi users in general. There were some valid suggestions that might help, however.
First off, if you can use an 802.11a router, you're less likely to have interference from other radio signals. The 802.11a routers run at 5 Ghz, while the 802.11b & g routers run on the 2.4 Ghz spectrum, making them more succeptable to interferance. You can also try different radio channels on your router to see if that helps.
One thing that did help was getting my router out of "mixed mode". Mixed mode provides backwards compatibility for 802.11b routers, but it slows down the network as a whole. Your router configuration may be different, but on my Linksys, it was a simple task to run in the faster "g" mode only. This will prevent devices that have a "b" radio from accessing your network, but it does keep things humming a little faster.
The other thing I did on my own (this wasn't indicated as a tip from Microsoft) was to enable Frame Bursting. Again, your router may not have this function or it may be called something different.
After trying to take advantage of the WiFi streaming for high-def, I'm a little disappointed. As I mentioned, the quality of the video is great, but only when you can see via your network. 802.11 a, b, and g standards for WiFi are getting a little old and tired. Additionally, the real throughput is essentially half of the advertised speed; and that's a best case scenario.
It would have been nice for Microsoft to offer a wireless network adapter with one of the newer WiFi standards, such as Super-G, MIMO, pre-N, etc.... I'm sure they will, but of course then I'll have to shell out more dollars and dump the $99 adapter I bought! In the end, I'll likely go with a wired connection, so watch for updates on the project.
If you have any other suggestions to help speed up the HDTV over WiFi, we're all
All the more reason to drop a line of ethernet behind the tv. Drill through the floor somewhere and pull the ethernet from your office. Or do what I do and put your 360 in your office. The wireless controllers work great going through my floors. Sure I have a set of video cables going up through the floor but it's all hidden behind my tv.
Great post, very timely. I've been researching this
a bit, and I'm wondering if anyone has experience
with the Netgear RangeMax suite of wireless products.
It purports to increase speed as well as provide
very fast speeds at longer (+50') distances.
What I've heard is that it is very difficult to
stream full HD content over a wireless network,
and that a wired network works much better. Your
post seems to support this. Unfortunately, I cannot
run a wire up to my office where the wap/net
connection is, so I am stuck with wireless.
Any thoughts? Thanks --J
Just goes to prove once agian wireless is about mobility not about performance and dependabitlity. Use wireless for your devices that require mobility and wired for everything else.
Save yourself a headace and run a wire.
The interesting thing is that 10/100 Ethernet only uses half of the pairs in a CAT5 cable so that leaves the other half for other things. Some use them to run power to their wap so it doesn't need to be near a plug. I use my extra pair to relay IR signals to my closet where my AV equipment is located.
I thought I read somewhere that you drop your total bandwith by half with each range extender you add to your wireless network. So if you are running in G mode at 54 Mbps, and you add one extender, your bandwith ends up dropping to 27 Mbps.
Anybody care to comment?
802.11 is by nature a bursty protocol which detects collisions from inteference and backs off speeds. Its not designed to support quality of service needed for constant udp streaming media. No matter how much bandwidth you can get, there's always going to be dips, and slight stuttering which will ultimately be unacceptable watching HD
I thought I read somewhere that you drop your total bandwith by half with each range extender you add to your wireless network. So if you are running in G mode at 54 Mbps, and you add one extender, your bandwith ends up dropping to 27 Mbps.
Anybody care to comment?
The linksys wireless G router with speed booster is said to boost the speed up to 108mb when transferring information across network by using two pipelines. Would that not apply to this situation? You are streaming media across the network? Does the router use have speed booster?
I fail to see why people say things like "I can't run a wire from X to Y." There's always a way to run ethernet..this coming from an ex-cable guy that worked for Comcast. Believe me, I can get a cable anywhere now, and usually do it in a way that you can't see.
Wireless = junk for things like this, and the review pretty much bears that out. Anything that's bandwidth and timely-delivery intensive is best left to wired connections.
The 360 has a wired ethernet port, so you can use a wireless game adaptor. While I don't know of any game adaptors that support the newer wifi standards, I don't think they are to far away. Additionally, some of the newer standards do give a measurable performance boost to old devices, I believe the boxes say 10-20%.
Truth be told, when it comes down to it I am going to go for wired too. I have wireless on my current xbox, but I think for full HD I'd be pushing it, as my computer and TV are on different sides of the house.
Another fix would be for MS and others accepting the MPEG4 codec as the standard for HD. I'm genuinely curious... what are the negatives that would come from doing this?
That kind of is a bummer. So many DVR's out there can't stream HDTV.
I was doing some research on this subject a whilea go about how to get HDTV streaming around the house and found this. I thought it was cool.
http://mocalliance.org/en/index.asp
What do you guys think? I mean... My house already has the cables so no need for Ethernet going all over the place. And no wifi problems.
Just my $0.02
tommiwan, I don't think it would matter if the router was a speed booster or 108 Mbps router. To use that functionality, the WiFi receiver must use the same technology as the router. The Microsoft hardware doesn't support any of the speed boost or SRX-type of signals. Of course, there's the idea for an expensive add-on from Microsoft down the line, no? :) Wired is the most stable way to go as some commenters have rightly point out.
I recall once reading that the signal from Wireless Routers are primarily in the horizontal plane. Anytime you go vertical signal strength drops quickly. From personal experience I know that I increased by wireless signal strength dramatically by placing my wireless router (which was in the basement) on a high shelf near the ceiling. Then placing my network adapter (external USB type) from my PC (located one floor up) on the floor. This minimized their vertical separation. If this is an option it may be worth a try.
Kevin, you can just add a wireless bridge of any manufacturer to the wired input of the Xbox360 and bypass the built in 802.11b/g/a wireless. The box thinks its connected via LAN, but the bridge transmits the data over 802.11n, SRX, rangemax, whatever you choose, back to a compatible router/AP where the media center sits
it is not technicaly half speed. the advriatised bandwidth is in megaBITS. most people measure in megaBYTES. a byte is 8 bits. therefore 54Mbps=6.75MBps. so it is a little more than half of the bandwidth. the reason that it is advratised as megabits insted of megabytes is one of consumer intellegance, meaning most people assume that the two are the same. so 54 looks better than 6.75. me i got lucky and installed a gigabit ethernet and couldn't be happier. 1Gbps=125MBps. and as a further note, there are different conversion types i am basing this all off of japineese conversions.
Dillon, I have some notes out to a few Microsoft Xbox MVPs as I was thinking the same thing. It all depends on if the 360 will work with the 3rd party hardware. If so, I may be upgrading my WiFi network and I'll certainly report back on the findings. Stay tuned!
I do have the rangemax 108… not the 360 yet… dying for one. But the performance is great I have two extenders (xbox and linksys) on my house working all the time plus my wife or my laptop…. My phone are 5.8ghz which helps..
Couple of things that might help. I have one hard drive for live TV or DVR only. Formatted in blocks of 64k. Which make fewer packages for the router to handle. Also, there is a new 85mbps wall plugged Ethernet bridge that I’ll be trying soon. http://www.netgear.com/products/details/XE104.php
I watched an interview of two guys on the Xbox 360 team on Channel9. BTW for those who have never heard of Channel9 (channel9.msdn.com), it is a site run by Microsoft employees that is filled with interviews of nearly all the dev teams at MS, and covers all their upcoming products. Most of them are very interestng especially if you are a Windows developer. I highly recommend checking it out. Anyway in this interview they said that for wireless media center extender functionality with the Xbox 360 that they only recommend 802.11a because it will give the best performance.
I would like to hear of someone's experience with an 802.11a connection. I just picked up a Netgear dual band AP/router that does 802.11g/a from Fry's Electronics for around $40 on sale, with the idea in mind that when I get an Xbox 360 and wireless adapter that I would already be set up for 802.11a. What was also attractive about the Netgear AP is that you can run both radios simultaneously becaause they are in different bands and you can dedicate the "a" radio to the XB360 and leave all your other wireless clients on the "g" radio. This would work fine for me because I have no wireless a adapters on or in any of my computers. I did however have problems with the Netgear, on wired lan, which would slowly reduce the bandwidth at which a very large (150MB) file would come in. It would begin at 160KBps or 1280Kbps or 1.25Mbps, which is my DSL's max downstream rate, and would decrease and eventually settle at 40KB. Anyone experienced this? So I plan on taking it back for a replacement and hope it was a hardware defect. Netgear's phone support seemed baffled. As soon as I switch back to my old router the speed shot back up.
I'm with #14 - that's the best way to go. A wireless bridge (aka ethernet bridge, aka gaming adapter) can be had for not much more than $99. I have a 802.11 Super-A/G bridge that works great with my SuperA/G router. This solution works pretty well in general. I'm supposed to get my 360 next week so I'll try it out then, but the benefit of a solution like this is you can "dedicate" the Super-A to the 360, and use Super-G for other devices so there isn't any bandwidth hogging going on.
Bigos – I’m running my Xbox 360 over 802.11a at home and am getting rock solid HDTV playback through a couple of walls. The main tricks to getting a good HD experience over wireless are: 1) use 802.11a - there's too much interference with 802.11g (microwaves, cordless phones, etc.), 2) use good wireless hardware (I have the Xbox 360 wireless adapter and Linksys WRT55AG, both of which have the Designed for Media Center logo), and 3) tweak your antennas to make sure they’re not in any wireless nulls (nulls = lower throughput)
Regarding speeding-boosting technologies (MIMO, Super-G, etc.) - none of these are industry standards (i.e. certified by the WiFi Alliance), so implementations vary from wireless silicon vendor to wireless silicon vendor, meaning that unless you have matched hardware at both ends, you often won’t get any speed boost at all.
To Ruben: The general rule of them is to expect no more than half the advertised speed. So, with 802.11a or g, don't expect more than 27Mbps of throughput . . . but likely, u won't even get that. I'm still on 802.11b, rated @ 11Mbps, so the "theortical" real world max is just over 5Mbps. In reality, where my notebook PC is about a foot from router, I started seeing loss in bandwidth from the maximum delivered speed by my cable operator, start to drop once advertised download speeds started to surpass 2Mbps. When my cable modem speeds were capped @ 3Mbps, I saw no more than 2.4-2.5Mbps via my wireless router. When the CM cap was lifted to 4.0Mbps, I barely saw more than 3.3Mbps over my Wi-Fi. Hope this real world info helps.
Bob: Most people measure speed, or more appropriately throughput, in terms of Mbps (bits). MB (bytes) are typically used to measure the size of a file for storage purposes, not transmission.