As of this month, 567 relays from our 2014 Tor Challenge are still up and running—more than were established during the entire inaugural Tor Challenge back in 2011. To put that number in perspective, these nodes represent more than 8.5% of the roughly 6,500 public relays currently active on the entire Tor network, a system that supports more than 2-million directly connecting clients worldwide.
Tor is a tool that protects privacy on the Internet by routing web traffic through a series of nodes, or “relays,†creating a network of servers that act as way stations on data’s journey from point A to point B.
Read more at Electronic Frontier Foundation