%% You should probably cite rfc3193 instead of this I-D.
@techreport{ietf-l2tpext-security-08,
    number =    {draft-ietf-l2tpext-security-08},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ietf-l2tpext-security/08/},
    author =    {Skip Booth and Glen Zorn and Dr. Baiju V. Patel and Dr. Bernard D. Aboba and William Dixon},
    title =     {{Securing L2TP using IPsec}},
    pagetotal = 28,
    year =      2001,
    month =     sep,
    day =       25,
    abstract =  {This document discusses how L2TP (Layer Two Tunneling Protocol) may utilize IPsec to provide for tunnel authentication, privacy protection, integrity checking and replay protection. Both the voluntary and compulsory tunneling cases are discussed. {[}STANDARDS-TRACK{]}},
}