Powerline networking products are quite popular in the European and Asian markets compared to the US. The Western Digital Livewire product was the first powerline product reviewed by AnandTech. In that piece, I had covered the various powerline networking standards currently in existence. The initiatives of the HomePlug consortium resulted in the IEEE P1901 standard and HomeGrid's efforts have led to the ITU G.hn specifications.

In the WD Livewire coverage, I had noted the lack of working silicon from any of the G.hn supporters as the prime reason for its struggles.

Over the last few years, many of the small powerline communication companies have ended up getting acquired by bigger corporations. Intellon was the pioneer of the HomePlug initiative, and Atheros bought them in December 2009 to augment their networking product portfolio. The powerline networking division of Conexant was purchased by CopperGate, who themselves were bought by Sigma Designs in October 2009. Gigle Networks was taken over by Broadcom, while DS2 found itself in Marvell's hands. ST Microlectronics has agreed to take over Arkados, and the only remaining player of note seems to be Spidcom. The powerline networking market is too small to support a lot of players, and it makes sense to bundle the technology with other networking offerings.

Atheros got hold of Intellon to create a hybrid networking platform. This is evidenced by the combo reference design (wi-fi router + powerline adapter) which has been adopted by Netgear and D-Link. Their future outlook involves the IEEE P1905 which is the convergent digital home network working group.

Sigma Designs is a more interesting story. IPTV has been at the core of Sigma Designs. Sigma created a vision with the set top box as the hub to power the new digital home. They acquired Coppergate to shore up the powerline networking side and Z-Wave technology for wireless home control transceivers.

Broadcom, Marvell and ST probably plan to use their PLC purchases to act as a one-stop-shop for their networking gear customers.

While Atheros is categorical in putting its weight behind IEEE P1901, the lineup from Sigma Designs is more interesting. When I visited Sigma Designs in October, I was shown some working demonstrations of HomePlug silicon, while G.hn silicon was shown at CES 2011. We will discuss Sigma's lineup first.

CopperGate got hold of HomePlug AV silicon through their Conexant acquisition, and Sigma Designs got into the fray through the acquisition of CopperGate. Their Homeplug AV product CG2110 was unveiled in October 2009 In October 2010, I visited Sigma Designs and had the chance to see a working consumer product based on that chipset.

The interesting aspect was ClearPath, and this enabled the product to work in a much more efficient manner even in noisy environments and Power strips are a major no-no for the Intellon/Atheros based networking kits, but the units demonstrated by Sigma actually seemed to like communicating through them! The demonstrated product was supposed to ship to consumers in November, but they are yet to go on sale. Sigma currently says it will begin shipping towards the end of February.

The HomePlug product from Sigma also seemed to perform better than the Intellon/Atheros solutions in noisy situations. The reason for this attributed to ClearPath technology which relies on proprietary algorithms to find a way around the noise.

It would be ideal If what I saw in the labs translates to real world performance when products based on the CG2110 hits consumers. It looks like Sigma Designs is a generation behind Atheros in the HomePlug AV market. However, they seem to be delivering what Atheros should have done in the first place. All said, controlled lab demonstrations can only be trusted to a certain extent. The performance of these units once they are sent to reviewers and end consumers will reveal the true story.

Even as CopperGate was acquiring Conexant's HomePlug technology, it was envisaging that G.hn would win the ultimate battle for wired networking technologies. After all, it was the proverbial holy grail, encompassing support for coax, phone lines and powerline in one product with promises of upto 1 Gbps bandwidth. In the above timeline presented by CopperGate in early 2009, it was expected that G.hn would completely replace HomePNA and HomePlug for phone and powerline networking in 2012. CES 2011 presented Sigma Designs / CopperGate with the ideal opportunity to show us what was being done towards achieving that goal.

At CES 2011, two companies demonstrated working silicon based on the G.hn standard. While Lantiq introduced the XWAY HNX100 series, Sigma Designs introduced their CG5110 chipset. I didn't have a chance to meet with Lantiq, and so, Sigma's CG5110 demonstration was the first time that I could really see G.hn in action.

Though both Lantiq and Sigma claim that their chipsets can be used over all three wired media (coax / phone lines / powerline), only Sigma seems to be backward compliant with HomePNA and HomePlug AV devices on the same network.

Sigma's Reuven Franco was kind enough to demonstrate the CG5110 in action over coax and also over a power strip. As can be seen in the photo of the setup I captured at the suite, the development board was hooked up to the Ethernet traffic generator. The actual application layer throughput was being measured in real time and updated on the spreadsheet.

Admittedly, the setup (power strip with no noise source and a plain coax cable) was not representative of real world conditions in general. However, it did end up giving us confidence in G.hn.

Sigma also indicated that ClearPath Extreme (the next generation version of the ClearPath technology they had demonstrated on the CG2110) wasn't yet enabled on the CG5110. They were quite confident that the test results being demonstrated (as shown above) would be experienced by consumers in real world situations also.

Working silicon is a good first step for the G.hn supporters. However, a multitude of challenges still needs to be overcome. In particular, we are not aware of the cost of backward compatibility with HPAV and HPNA (for the CG5110). Other G.hn silicon vendors seem to have completely eschewed backward compatibility. With the existing HomePlug install base, this is still an area of concern for G.hn. Also, the extent of interoperability of the CG5110 will only be known if Sigma Designs volunteers its silicon for interoperability tests / products get to the consumers. It is also not clear if the performance of the CG5110 is limited by the silicon and protocol overheads associated with interoperability.

There is always a cost overhead associated with integrating support for different media types on the same chip. So, it looks like HomePlug devices will continue to be cheaper for powerline-only communication. In the service provider market, the extra cost is probably a minor factor compared to the installation cost savings, but it will definitely be a factor in the price sensitive retail market. In addition, service providers also want software maturity (carrier-grade). It remains to be seen how long that will take for the G.hn vendors, but getting working silicon out of the door is a good start.

As Sigma Designs stole the powerline show at CES 2011, what was Atheros in the HomePlug camp upto? We undertook a visit to their booth to find out.

Unlike Sigma Designs, Atheros had no new silicon to show off at CES 2011. Instead, the focus was on increasing reliability and creating a better experience for consumers by making their current products run with better performance under adverse conditions.

Atheros termed this as 'Smart Link' technology. They indicated that this technology would roll out to all powerline adapters with 3 prongs. In simple terms, the current powerline adapters which are two pronged utilize the phase and the neutral wires for communication. The phase wire is affected by noise to a large extent. In case the ground wire is present, its usage over the phase wire can result in improved performance. Most surge protectors avoid any sort of filtering on the ground wire also. Smart Link technology determines dynamically whether the phase wire is affected with too much noise and decides to route through the ground wire.

Our biggest issue with Smart Link is that it will become available only on powerline adapters with three prongs. All the 500 Mbps offerings from Netgear and D-Link introduced at CES are two pronged versions. It appears that end users (who are purchasing the 500 Mbps powerline adapters in the North American market in the near future) will not be able to take advantage of 'Smart Link' even though it is only a firmware update.

When asked about next generation silicon in the powerline space, we were told that nothing new would be unveiled till the HomePlug AV2 standard gets ratified. In the meanwhile, Atheros is also working on their hybrid home network platforms (Hy-Fi) and the IEEE P1905 standard. While Atheros concentrates on HomePlug AV2 and IEEE P1905, it is the ideal time for G.hn silicon vendors to catch up.

Atheros Hy-Fi for Hybrid Home Networks

The slow rollout of the AR7400 based 500 Mbps powerline adapters in the North American market is also puzzling. As Brian Dipert of EDN notes, the firmware in the North American versions don't seem to be optimized for performance yet. It remains to be seen as to how Atheros and its customers handle this issue.

CES 2011 was quite exciting from the perspective of the powerline networking industry. G.hn silicon finally emerged from vaporware territory, and the initial demonstrations look promising. Of course, end products based on this silicon are probably 12 - 18 months away, but the threat for HomePlug is much more credible than what it was a year back. The absence of new silicon from the HomePlug vendors, as well as the distraction from IEEE P1905 will give a chance for the G.hn silicon vendors to catch up.

Though we didn't get a chance to look at Lantiq's offerings in the G.hn space, a look at their product brief [ PDF Link ] indicates that they are looking at their G.hn chip to enable hybrid platforms (extenders and multiple networking technologies in one product). The specs of the silicon from both Lantiq and Sigma Designs look similar. The backward compatibility with HomePNA and HomePlug AV/IEEE P1901 gives the Sigma silicon the theoretical edge.

It is the end consumer experience and improvements from proprietary algorithms such as ClearPath which will decide the winner in the G.hn silicon race. There are also a number of issues for G.hn itself to overcome in its fight against HomePlug. Interoperability with the already large installed base of HomePlug would be good, but this needs to be done without performance loss. It is good to see Sigma Designs taking the cue here and providing support for interoperability, but this should not be proprietary (as other G.hn silicon vendors don't want to implement this). There is still a lot of work left to be done in terms of software maturity and making the products carrier-grade. Controlling end product costs in the price sensitive retail consumer market will also be a challenge.

All said, we can't wait for G.hn products to hit consumers and the HomePlug forum to pull up their socks to counter the competition. It is an exciting time ahead for the powerline networking industry.