The companies backing G.hn--the ITU standard for home networks that rely on a home's existing powerline, telephone line, and coaxial cable--have for years been touting the technology's speed, versatility, and general suitability for high-bandwidth applications; particularly streaming media and online games. Up to now, we haven't been able to test any of those claims since there have been no consumer products based on the standard.
There is now, but Comtrend's PG-9172 Powerline ethernet Adapter is leading the G.hn charge in underwhelming fashion. While performing respectably in our Jperf tests, their average throughput of 265Mbps was well below the nearly 350 Mbps that D-Link's DHP-701AV delivered using proprietary enhancements to the rival HomePlug AV2 MIMO standard. The PG-9172 also was slower than ZyXel's PLA 5405. But it did manage to beat the stuffing out of Netgear's PL1200. The ZyXel and the Netgear are also based on the HomePlug AV2 MIMO standard.
On the bright side, the Comtrend PG-9172 is one of the most compact high-performance powerline adapters we've seen. These adapters require three-pronged adapters to deliver their best performance, because they make use of an electrical cable's ground wire to achieve maximum speed. LEDs indicate connections to power, a powerline network, and ethernet.
You can buy a pair of PG-9172s in kit form for less than $80, which is almost half the cost of a pair of D-Link's DHP-70, about $20 less than the ZyXel PLA5405KIT, and on par with the slower Netgear PL1200-100PAS. That's a pretty good deal viewed from the perspective of price/performance ratio. On the other hand, the G.hn standard has not yet gained significant traction in the home-networking market.
We've also yet to see real-world G.hn products based on the other types of wiring the standard supports: telephone wire and coax. You can already use coax cable (via the MoCA standard) to supplement your network, so it just doesn't seem like G.hn is adding all that much.