|At a Glance|
|Product||NETGEAR Powerline AV 500 Adapter Kit (XAVB5001)|
|Summary||HomePlug AV compatible, IEEE 1901-compliant powerline adapter kit with Gigabit Ethernet LAN port and higher maximum throughput than HomePlug AV|
|Pros||• Close to 100 Mbps of single-stream throughput
• HomePlug AV certified and interoperable
• Only about 20% throughput drop with distance
• Very low throughput variation in general
|Cons||• High throughput variation when adapters are close together (same room)|
My review of TRENDnet's first-to-market TPL-401E2K 500 Mbps powerline adapter kit ended with a question (actually two). Did TRENDnet's product really have design issues that caused its less-than-impressive performance? Or was Atheros' AMP 500 "500 Mbps" HomePlug AV compatible technology still not fully baked?
NETGEAR was finally able to get me an XAVB5001 kit (direct from Taiwan, no less). And to kill the suspense, it performs better than TRENDnet's adapters. But it also seems that Atheros still has some tuning to do, to bring out the full potential of its "500 Mbps" powerline technology.
The TRENDnet article has all the background on how Atheros' AMP 500 works, so I won't repeat it here. The gist is that it uses almost twice the spectrum that 200 Mbps HomePlug AV uses. So it can achieve higher throughput, if those higher frequencies can make it through your home's AC wiring.
The inside photo in Figure 1 of one of the two XAV5001 adapters in the XAVB5001 kit, shows an impressively heavy heatsink that's coupled to the main devices via a thick thermal pad. The heatsink isn't tied down; it is held in place only by the top cover.
This heatsink, plus generous use of vent grilles on all sides of the adpater should help keep the devices inside within proper operating range, even if the front cover of the adapter gets a bit warm to the touch.
Figure 1: Inside the XAV5001
Removing the heatsink reveals a familiar chipset (Figure 2): a large Atheros AR7400 MAC / PHY, flanked by an AR1500 Analog Front End (AFE) to its upper right and an Atheros AR8021 Gigabit Ethernet PHY to the lower left. If the XAV5001 hews closely to Atheros' reference design, there will be 16 MB of RAM and some amount of flash sitting on the bottom of the board.
Figure 2: XAV5001 board detail
There is actually another board on the very bottom of the package, connected to this top board by a 10 pin connector. The bottom board is probably where a lot of the AC line coupling and power conversion circuitry sits.
Setup And Administration
HomePlug adapters are factory set to plug in and go, and the pair of XAV5001's did. I had no problem with the adapters auto-negotiating Gigabit links with my Acer Aspire 1810T test notebook with Atheros AR8131 PCI-E Gigabit Ethernet controller and NETGEAR GS108 Gigabit switch.
Figure 3 shows a summary of the adapter's lights. Note that the three color signal quality light seen on some HomePlug AV roundup adapters and the TRENDnet TPL-401E is also incorporated into this product. Looks like a standard feature of the Atheros chipset.
Figure 3: XAV5001 ports and indicators
You also get a Security button that you can use to change the default "HomePlugAV" 128 bit AES encryption key. This is a good idea if you live in a dorm or apartment building where your powerline signal could stray beyond your home. The button doesn't change the security encryption strength, just the encryption key.
I didn't find a utility on the CD that came in the box. So I hit the XAVB5001 support page to download the 188.8.131.52 utility. I also downloaded the XAV5001 Firmware Upgrade Utility v184.108.40.206 while I was at it.
The utility is much fancier than TRENDnet's, but does essentially the same thing. I didn't get prompted to install WinPCap as I did when installing TRENDnet's utility. But perhaps that could have been because it had been previously installed.