It has been clear for many years that the big growth in building control networks is wireless.

Wireless networks are becoming increasingly reliable, and have the obvious advantages of flexibilty and ease of installation. However choosing the right wireless protocol is becoming a bit of a minefield.

What I want for Christmas is a single common open interoperable protocol, which
– has all layers of the stack clearly defined, including the application layer
– encourages distributed control
– has mesh routing
– has proper integrated security
– can easily be routed over the internet

For many years to two main contenders were Zigbee and Z-Wave. Zigbee makes a lot of sense – it is based on IEEE 802.15.4 which standardises the bottom two layers of the stack. We had great hopes for Zigbee, especially when it was used in the Nest learning thermostat. However it hasn’t gained the ground we hoped it would, and Z-wave is more popular in residential systems. One of the problems with Zigbee is that it doesn’t clearly define the application layer, so nodes from different vendors are not always interoperable. In fact many vendors appear to have locked down their implementation to avoid interoperability.

So now there are several emerging technologies that we are getting excited about:-

6LoWPAN (IPv6 over Low power Wireless Personal Area Networks) is aiming to standardise the use of IPv6 packets in IEEE 802.15.4 based networks. The great thing about this is the use of IPv6 (the current internet protocol), which makes routing over the internet trivial. However I’m concerned that it doesn’t go far enough in defining Mesh routing, or the application layer, to make products truly interoperable.

There is a group of companies (including the Nest people) developing Thread, a protocol built on 6LoWPAN which aims to to nail these problems – sounds good, but it is a closed group, and products must be certified, making it harder for the smaller guys like us to join in.

Bluetooth is also showing promise – originally intended only for personal use (connecting the devices you carry on your person), the new Bluetooth Low Energy (Smart) protocol is bridging the gap between personal and building products. Its big advantages are ubiquity (already available in smartphones, laptops etc), interoperability and security, making it easy to connect your smartphone directly to products in the building around you, such as lighting, heating and entertainment. And we’re hearing rumours of Bluetooth mesh…

So this is becoming like the VHS/Betamax horse race but on steroids! However this time I don’t think there will be a clear winner – a number of standards will co-exist, but there will be some losers and I don’t envy the developer/installer that backs the wrong horse…

Reminds me of the apocryphal proverb “may you live in interesting times”!