Posts Tagged ‘PowerLine Networking’

Linksys PLK300 – Failed attempt to be lazy

Tuesday, December 2nd, 2008

These days pretty much every home theater device has a wired Ethernet port. In my case there is a Xbox 360, a PS3, and a Panasonic Plasma TV that all need to be connected to the home network. Sure wireless has come a long way but nothing beats Cat6 for that delicious low latency/high throughput satisfaction.

Powerline networking is not a new technology, in fact home automation companies have been using it for years for things like turning lights on and off and security systems. Recently electronics manufacturers along with networking giants such as Cisco have formed an industry alliance "HomePlug", with the goal of pushing this technology out of the ‘obscure home automation catalog’ segment into the mainstream home segment.

HomePlug 1.0 is this alliance’s first "ratified standard" for this new version of an old technology. This technology is sold in kits and separate adapters, and promise different theoretical throughput levels (From 85Mbps to 200Mbps). Devices from Linksys/Cisco, NetGear, and Belkin (among countless others) have begun springing up all over the brick and mortar electronic retailers such as Best Buy within the last few months.

My experience with the Linksys PLK300 was a pleasant one. The Linksys PLK300 is a 200Mbps kit with one single port adapter and one four port adapter. It comes with everything you need to get started including Cat5 cables and stands for the adapters. Installation was a breeze and took less than 5 minutes. I connected the single port adapter to one of the outlets in my home office (cough: video game den…) and the four port adapter to an outlet near my home theater.

Using iperf (which is widely seen as one of the best tools to test throughput) I was able to achieve the following results.


As you can see the throughput achieved through the PLS 300 installation was actually worse than my current 802.11G Network (I didn’t think that was possible). I never considered it even remotely possible that I would achieve 200Mbps through this system, but less than 18% of the stated max throughput is a little silly. I will note that while the throughput of the connection was considerably lower, the latency was much better on the HomePlug connection versus the Wireless (802.11G) and did not vary as widely.

I contacted Linksys to see if perhaps there was something I was doing wrong. (The system is fairly foolproof but they’re making new fools every day…) I was told that perhaps the wiring in my built in 2003 home was too old or of poor quality and that I should be getting much more than 11.3Mbps (avg). I asked if there was some software or a way that I could see what "rate" the unit is connected at and the technical support representative indicated that this was not possible.

So it says on the outside of the box that the unit will do up to 200Mbps but there is no way of knowing what speed the unit is "linked" at? It seems like either they intentionally omitted including a "speed indicator" on the units themselves so that you won’t know what speed you’re getting unless you’re anal (like me) and test it.

It could also be that there is no sustained connection speed and that it constantly varies (like wireless). Still, it would be nice to know what level of quality the signal between the two devices is.

Ultimately, I decided to return my units as I found that the cost wasn’t worth the performance but I urge anyone who is in a similar situation that I am in to give these units a try. Linksys is one of the best home networking companies around, and it is very possible that the wiring in my McCondo is to blame for the throughput issues.

If you have a similar or different experience with these particular units, please note that in the comments.