The Zigbee Alliance has unveiled its latest Zigbee Pro 2017 specification, which now supports dual-mode devices that use the 2.4GHz band and the sub-GHz band. Zigbee has supported both bands for some time, but the dual-mode spec opens the door for a new breed of devices – as the Alliance looks to expand into new markets like smart cities. Notably, the spec unites the two separate approaches to Zigbee. The 2.4GHz band is used by the overwhelming majority of Zigbee devices, which in turn are mostly used inside households. The sub-GHz support has been used by some devices, but 2.4GHz was much more common – with sub-GHz Zigbee most commonly found in smart meters, acting as the link to the…