New technology helps trackers follow consumers' digital imprints — including across devices — through browser settings, battery levels and other details.
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Dartmouth College researcher Timothy Pierson holds a prototype of Wanda, which is designed to establish secure wireless connections between devices that generate data.
Eli Burakian/Dartmouth College
Yahoo Chief Information Security Officer Bob Lord on encryption: "Yes, it's used by terrorists. It's also used by people who are looking to voice their opinions on issues and to save lives."