@techreport{stenn-ntp-mac-last-ef-04,
    number =    {draft-stenn-ntp-mac-last-ef-04},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-stenn-ntp-mac-last-ef/04/},
    author =    {Harlan Stenn and Danny Mayer},
    title =     {{Network Time Protocol MAC/Last Extension Fields}},
    pagetotal = 8,
    year =      2019,
    month =     mar,
    day =       25,
    abstract =  {NTP packets can be authenticated by a Message Authentication Code (MAC) if a MAC is present at the end of an NTP packet. The legacy format for this MAC is not formatted as an NTP Extension Field, and its presence may cause some implementations a parsing ambiguity. This proposal introduces two ways to resolve this problem. One is to provide a MAC Extension Field. The other is an extension field that unambiguously declares itself to be the last extension field in an NTP packet (so any additional data MUST be a legacy MAC). RFC EDITOR: PLEASE REMOVE THE FOLLOWING PARAGRAPH BEFORE PUBLISHING: The source code and issues list for this draft can be found in https://github.com/hstenn/ietf-ntp-mac-last-ef},
}