Review: Using powerline adapters for home networking
Today's powerline networking devices work as advertised and are ridiculously easy to use -- but don't try to mix and match technologies
Instant networks
What did happen on a day-to-day basis was automatic network configuration when more than two powerline adapters were used at a time. When three or more are in use, they form a sort of client/server network. The first adapter would be the server or master, and the others would function as clients. That meant the first one could be plugged into a port on a router, and the others could be plugged into various PCs, which then automatically networked back to the master and through it to the router and out to the Internet.
The HomePlug units networked together regardless of brand, and units from any of the three vendors would serve as the master, with units from the other vendors serving with it as clients. I wasn't able to try that with the UPA units (because I had only two) but was informed that they also automatically configure themselves into networks.
The downside is that I couldn't get two point-to-point connections working simultaneously, such as connecting from two ports on a router to two different PCs. The units appeared to interfere with each other and throughput slowed to a crawl.
Meanwhile, the UPA units and the HomePlug units interoperated only grudgingly. When UPA adapters were already operating and I plugged in HomePlug adapters, the UPA adapters continued functioning normally. The HomePlug devices, presumably treating the UPA signals as noise, slowed down. When HomePlug adapters were already operating and I plugged in UPA units, the UPA units didn't function at all, while response times for the HomePlug units were about four times slower.
Complications
All the units came with software, the chief purpose of which was to change the encryption passwords of the adapters. The HomePlug units use 128-bit Advanced Encryption Standard encryption, and the UPA unit used Triple Data Encryption Standard encryption, with 168 bits. Either would make the CIA proud.
The main reason for encryption is for situations where other people in your neighborhood are using powerline adapters, because every house connected to the same power company transformer is basically on the same circuit. (In the U.S., the average is five homes per transformer.)
Some of the software modules also let you scan the network, identify all the adapters and see what speed they were maintaining. But unless privacy was an issue, there was really no reason to even load the software.
In actual use, the main drawback I found with the devices was that they took up scarce power outlets -- they didn't have through-plugs. On the other hand, they did work fine with power strips and extension cords, although the instructions warned against trying to plug them into uninterruptible power supplies or surge protectors, either of which would make hash of the signal.
Lamont Wood is a freelance writer in San Antonio.
Copyright © 2007 IDG Communications, Inc.