%% You should probably cite draft-ietf-ntp-mac instead of this I-D. @techreport{aanchal4-ntp-mac-03, number = {draft-aanchal4-ntp-mac-03}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-aanchal4-ntp-mac/03/}, author = {Aanchal Malhotra and Sharon Goldberg}, title = {{Message Authentication Codes for the Network Time Protocol }}, pagetotal = 12, year = 2016, month = oct, day = 26, abstract = {The Network Time Protocol (NTP) RFC 5905 {[}RFC5905{]} uses a message authentication code (MAC) to cryptographically authenticate its UDP packets. Currently, NTP packets are authenticated by appending a 128-bit key to the NTP data, and hashing the result with MD5 to obtain a 128-bit tag. However, as discussed in {[}BCK{]} and {[}RFC6151{]}, this is not a secure MAC. As such, this draft considers different secure MAC algorithms for use with NTP, evaluates their performance, and recommends the use of CMAC-AES {[}RFC4493{]}. We also suggest deprecating the use of MD5 as defined in {[}RFC5905{]} for authenticating NTP packets.}, }