Wednesday, July 18, 2007
Summer: The Winter Of My LAN Discontent
As you'll see in two weeks (and one day), as Maury's already alluded, I was pretty durned impressed with the incremental performance and reliability improvements that have marked the powerline network progression from HomePlug 1.0 to Intellon's proprietary HomePlug 1.0 Turbo, and from there to today's '200 Mbps' triumvirate of HD-PLC (i.e. Panasonic), HomePlug AV, and UPA (i.e. DS2). But, although powerline networking exhibits tremendous promise (which is why I follow it as closely as I do....what could be simpler than using your AC-fueled gadget's existing power connection to also network-tether it?), if my experiences of recent days are any indication, it's still bedeviled by compatibility glitches of the sort that I've mentioned on numerous past occasions.
A month ago, I mentioned that I gave up trying to tether my two D-Link Internet webcams to my Linksys WRT54GC router over Wi-Fi, instead turning to HomePlug 1.0 Turbo-based connections. At the time, I indicated that I'd uncovered only one powerline 'glitch'; the DCS-5300W's Installation Wizard utility was no longer able to 'see' its respective webcam. After I got back up here yesterday and began exploring the situation further, I realized that the problem was even worse than I'd originally thought.
If I connect my laptop to the network via a powerline spur (i.e. within the same powerline topology that the webcams reside on), I can 'see' the webcams just fine. If I direct-connect my laptop to the router over CAT5, I also can 'ping' the webcams, HTTP to them, locate them with configuration utilities, etc. But, if I connect the laptop to the router over Wi-Fi, the webcams completely disappear from the network (at least according to my laptop, that is).....unless I use my WAN address to access them (since I have firewall 'holes' in place for them). In which case, they magically reappear.
I'd normally blame the router, but my HD DVD player and ReplayTV are also powerline-tethered, and my laptop can see both of them just fine via Wi-Fi. I'd blame the powerline adapters (Aztech's HomePlug 1.0 Turbo adapters and Actiontec's HomePlug AV adapters both exhibit the problem), except that I've not seen this same issue with any of the powerline networking setups I've ran over the years back at my primary home office. The biggest difference between there and here is that in Sacramento, none of the various routers I've employed have ever included Wi-Fi capability; I've always used discrete wireless access points.
Sigh. This stuff has got to drive technical support folks nuts.
p.s....oh, and one thing I forgot to mention; with the HomePlug AV adapters, the webcams' performance (measured both in terms of video frame rate and in the load times for various web browser-based configuration screens) was atrocious until, on a hunch (don't ask me how I came up with this idea, as I haven't a clue), I disabled UPnP at the router. Smooth sailing ever since....
Followup: I've rebooted the router, and I'm now able to 'see' the DCS-5300W webcam via its LAN address even when my laptop is connected to the router via Wi-Fi. However, I'm still not able to 'see' the DCS-1000W webcam unless I use the WAN address trick. I also changed the router's broadcast channel from 11 to 1 (nearby faint APs are all broadcasting on channel 6) and the new EDN laptop is now also reliably conecting to the WRT54GC. So I've made some progress, although the reasons why aren't particularly clear....tomorrow's another day, and I hope I don't encounter a one-step-forward-two-steps-back scenario (or even a two-steps-forward-one-step-back situation!) in the morning. G'night.
Followup: It's reassuring to read that I'm not the only tech journalist to fall into the black hole of baffling problems and fixes.
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