Data and Drones

Microsoft CEO Satya Nadella seeks to reassure European customers over security and privacy with local data centres. Facebook's top engineer Jay Parikh on why he thinks laser-equipped drones are the way to bring the Net to remote places. And physicist Professor Brian Cox on the tantalising promise of quantum computers. Presented by Rory Cellan-Jones with special guest tech writer Kate Bevan. (Picture: Facebook's Jay Parikh),