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The Graveyard - Products No Longer Supported => Routers / COVR => DIR-855 => Topic started by: moosic on February 18, 2008, 06:20:43 PM

Title: dir-855 with media center extender
Post by: moosic on February 18, 2008, 06:20:43 PM
I'm hoping to use my dir-855 with a Vista Media Center pc which is connected via a dap1555 to the wireless network.    The last piece of the wireless network is a linksys dma2200 MC extender. 

Question:
Do you think I'll get stutter free high def TV?  My router has been recalled.  I couldn't connect to the 5ghz network due to the issue that I hope is fixed by the recall.
Title: Re: dir-855 with media center extender
Post by: AWDL on February 20, 2008, 09:58:19 AM
I would never suggest HighDef over wireless (even at 5GHz). HighDef is very suseptible to packet loss, a wired connection would be your best hope for "studder free" connectiivity. I would think SD should not be a problem though.
Title: Re: dir-855 with media center extender
Post by: Lycan on February 20, 2008, 10:23:31 AM
The average HD stream requires about 30-35 MBps. Even if you had a perfect signal and a 300N connection, thats still only about 38MBps. So that one stream would eat your whole pipe.........
Title: Re: dir-855 with media center extender
Post by: moosic on February 23, 2008, 08:45:24 AM
Well that is a bummer.  All of your marketing materials for the DAP-1555 state otherwise.  It even mentions multiple high def streams.

"BENEFITS OF DUO
Xtreme N Duo™ is the latest addition to the Award-Winning Xtreme N product family. The DAP-1555 works with next generation dualband (2.4GHz and 5GHz)** 802.11n wireless devices as well as legacy 802.11a/b/g products. The D-Link® Xtreme N Duo MediaBridge™ is designed for users looking to get a true HD wireless connection that can handle multiple High-Definition video streams throughout the house."
Title: Re: dir-855 with media center extender
Post by: AWDL on February 25, 2008, 03:59:23 PM
"Video streams" should be changed to "multimedia streams". Yes you can run multiple, but you said Stutter free. For the demand I would suggest a wired connection, but theorectically the pipe will be better suited for HD than if you had a DI-614+ and a DWL-900AP+.
Title: Re: dir-855 with media center extender
Post by: Sir Wells on February 26, 2008, 01:09:21 AM
Hi,

Sorry to jump in like this, but I just want to say that I measured my 802.11n network at home and it fluktuates in between 80 and 140 Mbps actual data speed. (Not raw sync speed) It is well enough for multiple HD streams. The problem with wireless is more often if you run Multicast streams where the packages cant be resent, that will give you pixeled picture or suttering sound.

My setup: DIR-655 + DWA-547 + DWA-650 + AR5008 AGN (Macbook pro)

Measurement tools: Jperf + timing file tranfers.
Title: Re: dir-855 with media center extender
Post by: FromAtoN on March 08, 2008, 08:54:13 AM
The average HD stream requires about 30-35 MBps. Even if you had a perfect signal and a 300N connection, thats still only about 38MBps. So that one stream would eat your whole pipe.........

Your marketing department needs to be terminated and replaced based on your claims.  I don't buy into the hype myself but there are many people that will see your HD claims and buy the inferior product. >:(

See for yourself:
http://www.dlink.com/products/?pid=548


"The Duo technology in the DIR-855 supports dualband (2.4GHz & 5GHz) wireless signals at the same time. This allows you to check e-mail and browse the Internet using the 2.4GHz band while simultaneously streaming High-Definition (HD) movies and other media on the 5GHz band. The DIR-855 is designed for users looking to get a true HD wireless connection that can handle multiple HD video streams throughout the house,"...
Title: Re: dir-855 with media center extender
Post by: Fatman on March 10, 2008, 10:47:51 AM
I believe there may be some confusion in that source quote.

To my knowledge HD streams pull in at around 35 Mbps not 35 MBps (notice the difference, that capital B means that it is 8x the lower case b size)

The PHY speed of Draft N is 300 Mbps or 37.5 MBps (300mbps * 1 Byte / 8 Bits)

This allows for a potential of 8 streams at full HD and still below the max throughput.

Naturally you will never see this max throughput, however the only physical test I see in this thread shows that Sir Wells was getting between 80 Mbps and 140 mbps.  This is enough for more than 2 streams in the worst case scenario.

The advantage of going with a Duo product is that you can devote an entire Draft N network on it's own frequency to just HD traffic and still have your trusty 2.4 Ghz Draft N connection unaffected.

In other words I don't see where the problem is, if you are going to want to stream HD wirelessly (which AWDL and I don't recommend due to the fact that wireless is so susceptible to interference which might interrupt your viewing pleasure) then this is THE BEST solution on the market.  However a wired connection is preferred if you want a smooth viewing experience.
Title: Re: dir-855 with media center extender
Post by: AWDL on March 10, 2008, 01:11:40 PM
Fatman,

I was stuck on studder-free. I was just trying to suggest my truest technical opinion. Even a cable might not be studder-free, but I thought the customer was focused on studder-free so I backed away from wireless solutions as the suggestion.

I can't fault Marketing (this time) because there is plenty of pipe for HD streams. Marketing can't claim studder-free in ALL environments.

Remember I can make wireless not work, if you let me get close enough to the AP or client.

-AWDL
Title: Re: dir-855 with media center extender
Post by: Fatman on March 10, 2008, 01:22:33 PM
I absolutely agree with you, I was just trying to back up the fact that the marketing material is based on the fact that this is the best wireless solution.

Then I put a long disclaimer that the best wireless solution is still not a solution.

P.S We both know you don't have to be very close at all to either to completely destroy a wireless connection if that is your intent.