"DNSCrypt is an open source DNS encryption client program
offered by OpenDNS, a third-party DNS provider, to prevent DNS
snooping, spoofing, and other man-in-the-middle attacks. It does
this by completely encrypting the DNS traffic to and from a user's
computer and the OpenDNS servers. The encryption wraps itself
around the DNS traffic much like SSL wraps itself around HTTP
traffic, though DNSCrypt is using another form of encryption: a
type of elliptic-curve cryptography, called Curve25519.