About: http://webisa.webdatacommons.org/143022066

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Instead of a key at the sending end, there is a light source to convert electrical pulses to light, and at the receiving end there is a light-sensitive receptor that converts light to electrical pulses.
http://www.w3.org/ns/prov#wasQuotedFrom	metafilter.com