We have for many years been proponents of “open”, “connected” and “distributed” building control networks:-
“Open” meaning it conforms to open published communication standards, so that a range of products from different vendors can be used together in a single control system.
“Connected” meaning systems can connect to other systems and to the outside world, allowing integration and remote control and diagnostics. This can mean gateways, that translate communications between different closed systems, or Routers if the systems use the same protocols, i.e. how the internet works….
“Distributed” meaning that the control decisions and communications are spread out across the system (the light switch talks directly to the light bulb), as opposed to there being a master control node. There are many advantages to this, such as reducing network traffic bottlenecks, avoiding single points of failure, and reducing system costs.
We prefer wired solutions for the more robust commercial systems we design, where cost is less of an issue. We were therefore big fans of LonWorks, using it for a number of large system designs in the 90s-00s. Whilst it was not originally an open standard, it was eventually published as ANSI/CEA-709.1 and a number of vendors launched interoperable Lon products. However it never gained market dominance in general building controls, and much to our frustration it appears to be falling out of favour. There are still the old favourites like Modbus, BACnet, Profibus, KNX and of course a plethora of IP over ethernet solutions, but no clear leader. KNX is currently my favourite but again the range of vendors is quite limited, and there are interoperability problems.
So the latest fashion seems to be finding various ways to mix&match protocols. For example Echelon is pushing the IzoT platform, which offers (amongst other things) routing of BACnet over LonWorks. I can see why they want to do this, as it keeps them in the race, but these systems are getting complex!
With the advent of the phrase “Internet of Things” this has become a rapidly changing market, and I am hoping that a dominant protocol will emerge, that everyone adopts. And please pretty please can it use IPv6