DNSCrypt is a network protocol that authenticates and encrypts Domain Name System (DNS) traffic between the user's computer and recursive name servers. It was originally designed by Frank Denis and Yecheng Fu. Although multiple client and server implementations exist, the protocol was never proposed to the Internet Engineering Task Force (IETF) by the way of a Request for Comments (RFC). It also mitigates UDP-based amplification attacks by requiring a question to be at least as large as the corresponding response. Thus, DNSCrypt helps to prevent DNS amplification attacks.