At the end of last week, we spoke to GreenPeak CEO Cees Links about the smart home in general and GreenPeak’s ZigBee ambitions in particular. We were told in no uncertain terms that the smart home was happening, and that the potential market is huge ‘ 600 million homes, an average of 100 devices per home, resulting in 60 billion potential nodes. With GreenPeak currently shipping 1 million ZigBee chips each week to OEMs, we’re certainly prepared to lend its CEO our ears.
The GreenPeak projection for the smart home consists of three overlapping phases, on a time frame that we think can only reflect the homes of affluent westerners and not the average home of the average global citizen. But that of course makes absolute sense, as the smart home itself is most likely to make it to customers as part of a pay TV or internet offering ‘ it won’t be long until triple and quad play are joined by a ‘quint’ play offering where home automation is offered on a subscription basis.
The issue of who exactly would be at the heart of the ecosystem arose in conversation, with Links confirming that GreenPeak was targeting pay TV operators and ISPs who were looking to add smart home offerings to their subscription packages. As both would have CPE installed in the home, they are uniquely placed to infiltrate the customer home without having to depend on a consumer buying a separate hub or box ‘ rather a consumer would find themselves with the appropriate smart home equipment (in the form of a home gateway or set top), which the operator could then leverage to push a subscription home automation package.
Links observed that there are many brands which are looking to subvert this model and enter the smart home ecosystem directly, although he believes that the operators are much more strongly placed to seize the emerging market than the likes of Samsung.
Phase 1 of GreenPeak’s vision spans 2012-15, where a ZigBee based set top or home gateway is placed in the home. Phase 2 sees that unit serve as a central hub for security and energy management, at some point during 2013-2018. The final phase spans 2015-2020 and will see the set top govern and fully integrate the home’s environmental management and security.
GreenPeak manufactures a range of ZigBee modules for different implementations in the home. The 7 series is the chip found in the set top or gateway. Comcast uses the GP711 in its X1 set tops to link to the ZigBee remote control that is supplied with the unit. The GP501 serves as a ZigBee transceiver, which forms the backbone of the mesh network that the GP410 and other 4 series use to coordinate with the 7 series chips that form the heart of the ZigBee mesh.
Each series of modules uses a slightly different method of communication, tailored to fit the intended application. For instance, the Comcast remote control uses the low-latency RF4CE protocol (radio frequency for consumer electronics), due to its need for a speedy user experience, whereas something like a window latch will use ZigBee Pro ‘ as it only requires very small data rates but needs a long lasting battery life.
ZigBee is an (almost) open managed standard used by a number of vendors, including GreenPeak, Atmel, Freescale, Texas Instruments and Silicon Labs. Membership of the ZigBee Alliance requires an annual fee but provides early access to new developments and specifications of the protocol. By comparison, Z-Wave is a proprietary standard developed by Zensys, later bought by Sigma Designs, itself a Siemens offshoot. The standard is available to Sigma customers,
ZigBee broadcasts in the unlicensed 2.4GHz spectrum globally, but uses other bands according to geographic regulations including 915MHz in the Americas and Australia and 868MHz in Europe. Moving out of the 2.4GHz spectrum entirely may become a preferential option if home WiFi network congestion becomes an increasing problem for smart homes.
The ZigBee protocol, very closely based on IEEE 802.15.4, specifies sixteen 5MHz channels are allocated for use in the 2.4GHz range, using offset quadrature phase-shift keying (OQPSK) for lower amplitude fluctuations, while binary phase-shift keying (BPSK) is used in the lower frequency allocation, as it is the most robust form of phase-shift keying and requires the most noise to distort the signal ‘ at the expense of data rate.
Links was adamant that only an open standard such as ZigBee could prevail in IoT, largely because economies of scale are harder to come by in proprietary ecosystems. He was also not shy in criticizing Z-Wave for this very reason, noting that it was rushed to market and isn’t secure enough for the home. ZigBee has enjoyed more R&D, which Links feels makes it the superior ecosystem and product. Another point of contention for Links was that a Z-Wave chip costs around 5 times as much as its ZigBee equivalent.
We asked Links if ZigBee could peacefully coexist with the likes of Z-Wave, and he replied that there was no need for wireless protocols other than WiFi, ZigBee and Bluetooth. In that order, the 3 protocols provide communication for the 3 personal spheres that they occupy ‘ outside the home, inside the home, and wearables and device interfacing.
The personal sphere would use Bluetooth Low Energy (BLE, now rebranded as the frustratingly misleading Bluetooth Smart) for instances where a person in the house would need to interact with a device in the connected home. For example, the wireless key fob used to open the front door would use BLE to activate the lock, but the lock would relay its status information to the home via ZigBee.
As Bluetooth is the established protocol for smartphones and the wearable devices that are linked to them, Links does not see ZigBee replacing BLE in handsets or other devices such as key fobs. Bluetooth is too ingrained in the ecosystem for ZigBee to replace it, and to that end Links does not see BLE and ZigBee as true competitors ‘ he thinks they both have their own spheres and specialties.
The BLE-activated door lock would communicate with a central device in the home that acts as the coordinating hub for the ZigBee mesh. This hub would in all likelihood be a set top or broadband gateway in the ideal smart home, and it would use its internet connection to link the home to the outside world. The hub would contain all of the radios needed to communicate with the rest of the smart home, and it is in the OEM’s interests to settle on as few protocols as possible, to reduce the bill of materials. Links’ vision requires 3 radios (perhaps more depending on the WiFi architecture), whereas something like the Revolv hub currently needs 7 to cover all bases in the smart home. Less radios means lower bill of materials.
But moving beyond the home, Links feels that ZigBee is not yet mature enough to branch out of the home and into the city. He noted that it needs to be ‘industry hardened’ before it can be installed and trusted to govern mechanisms such as traffic control and lighting without security concerns that might be orders of magnitude more dangerous than a single home being compromised. The consequences of a home window being hacked and unlocked leading to a burglary are one thing (especially when you consider that a hammer or a brick would achieve the same end) but a communication system must be very secure before it is trusted by municipalities. In particular, the end devices of a ZigBee network need to be secure from unauthorized access as a malicious attack could reach the heart of a ZigBee network from any point in the mesh. This would be easier inside a home where you can keep people out, but much harder in a city. We feel that Links believes this is not a stage that ZigBee has yet reached, but one that is not far away.
As for the future of GreenPeak, Links said that the company remains focused on catering for the smart home. When prompted he said that although there were healthy profits to be made in the million ZigBee chips he ships to OEMs each week, GreenPeak was choosing to channel a lot of its returns into future R&D. In that regard, profitability is a secondary goal. Links was keen to differentiate the company from the TIs and Intels of the world.