CEDIA 2015: KNX Demos Access Control Via IP-Based Door Bell With Video, KNX ProtocolOctober 16, 2015 | Home / October 16, 2015 rave-video / CEDIA 2015: KNX Demos Access Control Via IP-Based Door Bell With Video, KNX Protocol CEDIA 2015: KNX Demos Access Control Via IP-Based Door Bell With Video, KNX Protocol