The Next Gen of Powerline Network Adapters

The HomePlug AV specification is the latest in a series of HomePlug powerline adapter specifications. On a quiet line, HomePlug AV can get a throughput of 80 Mbps, which is enough to connect multiple HD-TV sets to a digital set-top box.

The HomePlug Powerline Alliance has a Web site listing of products that support the HomePlug AV spec from more than a dozen vendors. The three products listed offer 128-bit Advanced Encryption Standard (AES) encryption, with software that lets you set the encryption key.

Also, in point-to-point connections, all three adapters immediately replaced an Ethernet cable as described. Even when a hair dryer was plugged into the same outlet and turned on, all three adapters continued to function without a hitch.

But when two ports on a router were connected to two adapters so that downstream they were connected to two different computers, the units interfered with each other. Also, response times rose by a factor of 50. When one adapter was plugged into a port on the router, multiple adapters downstream could use the upstream adapter as if it were a router, with the adapters basically creating their own network. In fact, you can use as many as 16 adapters in a network.

The only UPA adapter tested was the HDXB101 from Netgear. In point-to-point use, it behaved much like the HomePlug units, with one difference: A plugged-in and running hair dryer brought the unit to its knees. In fact, once the hair dryer was turned on, response times went up by a factor of about 150.

Netgear states that 16 of the units can network in one circuit, like the HomePlug units. Also, downstream UPA adapters can network to the upstream UPA adapter.

In conclusion, it appears the two specifications shouldn't be mixed. nPlug it In, Plug it In

HomePlug AV Units

• Actiontec Megaplug HPE200AV Ethernet Adapter from Actiontec Electronics. Standard direct-plug. Price: Just under $170 for two-unit kit

• PLK200 PowerLine AV Ethernet Adapter from Linksys (division of Cisco Systems). Direct-plug unit. Price: About $180 for two-unit kit

• PLA-400 Ethernet Adapter from ZyXEL Communications. Uses power cord. Price: About $100 for individual units

UPA Unit

• HDXB101 from Netgear. Direct-plug unit. Price: About $200 for a two-unit set

LAMONT WOOD is a freelance technology writer based in San Antonio.