Sigma Designs has joined the Open Connectivity Foundation (OCF) in a move that further opens up the Z-Wave low-power mesh protocol to smart home developers. Joining the OCF, which recently swallowed its AllSeen Alliance rival, Sigma is hoping to drive demand for Z-Wave chips – of which it is a major manufacturer. The OCF now manages both IoTivity and AllJoyn, two standards for defining device discovery and communication frameworks that sit above the radio-layers of the end-devices. As it stands, the OCF has direct partner relationships with Z-Wave and Thread, although certification and product adoption announcements have been slow to materialize. This is another step forward for smart home standards consolidation, and while the upper-layer frameworks have come together, there’s…