%% You should probably cite draft-ietf-ntp-mac instead of this I-D.
@techreport{aanchal4-ntp-mac-00,
    number =    {draft-aanchal4-ntp-mac-00},
    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/00/},
    author =    {Aanchal Malhotra and Sharon Goldberg},
    title =     {{Message Authentication Codes for the Network Time Protocol }},
    pagetotal = 7,
    year =      2016,
    month =     jul,
    day =       8,
    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 not a secure MAC. As such, this draft considers different secure MAC algorithms for use with NTP, and evaluates their performance. Given the security concerns, we also suggest deprecating the use of MD5 as defined in {[}RFC5905{]} for authenticating NTP packets.},
}