• Case study: Extending wireless coverage in a huge home with powerline networking

    Wireless networks can be a beautiful thing, or they can be an incredibly frustrating thing. In this case study we'll look at how powerline networking was used to extend wireless coverage in a very big log house with thick logs walls and lots of tile, where running cat5 cable was not an option. For those not familiar with powerline networking, rather than running cat5 network cable, you simply plug a network adapter in to the wall at each location where you want to transmit and it uses your home power cabling for network communication.

    The subject in question for this case study was suffering from abysmal wireless performance. Laptops used upstairs would consistently drop connections, streaming internet radio (via Sonos) would constantly buffer, and the wireless printer in the study would work marginally at best. To try and fix the problem a Belkin F5D7132 Wireless-G extender had been put in to place, in extender mode. This appeared to work sometimes, but most of the time wireless performance was still extremely frustrating.


    Before digging in to the problem and providing a solution, I figured I would look at all factors. This was a little over a year ago, so I had different options at the time. Price wasn't a concern, as long as it wasn't too out there. More of the concern was the log walls, the tile, and the robust construction of the house, with no possibility to run cat5 cable. I decided to make a diagram of what I was starting with.


    Obviously having the 2 Sonos ZonePlayers on wireless when they are right next to the switch is senseless, especially since the homeowner likes to stream internet radio via Sonos. The wireless extender extending over wireless is painful too. It's halving the bandwidth for transmit and receive, plus it's on the same channel as the main router. Half the time it's searching for signal as it can't pick up the wireless signal. When it does pick up signal it's terrible. At the PC in the electronics closet I can get the full internet download speed with speedtest.net, upstairs on a laptop it will register at a tenth of what it is downstairs, that is, when I can get it to work. The Sonos network and router also conflict with each other at times, with the router on auto select for the channel.

    The router in the basement electronics closet is another big bummer. The house is new, the owner didn't think of cat5 cabling when building as someone sold them on wireless, and they are pretty concerned with aesthetics. Not only that, but the wireless router is showing signs of age, sitting with my laptop 6 feet away from the router I'll see ping times of > 200ms and occasional timeouts. The wireless extender is on the main floor, in a strategic line-of-sight place in relation to the router that should be good for signal.


    My proposed solution:


    Replace the aging Belkin router with a Buffalo WZR-HP-G300NH on channel 6, which the FCC report shows is the highest transmit power
    Add in a D-Link 8-port gigabit switch (they have nothing gigabit now, but it's cheap and leaves room for the future)
    Put the 2 Sonos ZonePlayers on wired and get them off wireless, set Sonos to use channel 1 for their mesh network.
    Get the NetGear XAVB2501-100NAS powerline network set and put one at the router and one at the wireless extender (I verified no AFCI breakers as they can greatly diminish powerline performance), so at least the wireless extender should be able to serve good wireless to the main level. Run the wireless extender in AP mode on channel 11.

    Here is diagram of the end solution, subtle changes, but hugely effective.



    So how well does this work? Extremely well... The figures below were taken with a Dell Latitude D630 laptop and Intel 5300 wireless card set in wireless G mode running XP, to a nothing-special Dell desktop running XP and a 10/100 Intel NIC, plugged in to the internet router. The wireless G and the 10/100 NIC are quite obviously the bottlenecks, and the reason for the figures. The figures were taken with LAN Speed test, which is good for a baseline, but can not be accepted as the absolute fact as it uses SMB filesharing to attain its numbers. This is even more obvious with the powerline figures actually being faster on read than wired in cat5 direct, so take them with a grain of salt, but they are good for baselines.


    Transport Write speed Mb/s Read Speed Mb/s
    Wireless G to router (6 ft. from router) 30.98 28.62
    Wireless G to extender, then over powerline to router (6 ft. from extender) 32.15 28.12
    Laptop plugged directly in to powerline in place of extender, powerline direct back to router 50.46 42.42
    Laptop plugged directly in to same router as Dell desktop 86.28 36.11


    Would I do anything different with what is available today? A few things... First, the Netgear powerline adapter to the Belkin wireless G extender is ugly for aesthetics, and it's only wireless G. To be honest, that's more than enough for the internet connection here, but it could be better. Today I might sell the homeowner on the Netgear XAVN2001 wireless-n extender. Maybe if Netgear wants to send me one I can put it through its paces and see if it can improve on what we already have?

    I'm also a big fan of the Vortexbox and would probably try to point the homeowner in that direction due to its Sonos server capabilities and the CD ripping and album art downloading qualities. The XP has worked ok for them, but it has two problems. First, they also rent the place out, and renters somehow keep getting on to the box for internet browsing despite setting passwords. This leads to spyware and constant configuration problems. Additionally, the internet is a satellite internet solution as it's in a remote location, and even with the small amount of Windows updates, they often go over their monthly download quota when also streaming internet radio.

    The jist of all of this is that using powerline networking can greatly improve your wireless coverage, and wireless extenders that are not hardwired in (either via powerline networking, MoCa, or cat5) just won't cut it. When at all possible I try to move whatever I can off wireless, so that things like laptop wireless usage can go off without a hitch. In the future I'd like to try a powerline networking switch for audio/video devices where running cat5 is not possible.
    Comments 1 Comment
    1. sparkgates's Avatar
      sparkgates -
      Thanks to sharing this adorable information by this thread i get more knowledge about wireless networking ,point to multi-point wireless,point to point wireless.
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