%% You should probably cite rfc6188 instead of this I-D.
@techreport{ietf-avt-srtp-big-aes-06,
    number =    {draft-ietf-avt-srtp-big-aes-06},
    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-avt-srtp-big-aes/06/},
    author =    {David McGrew},
    title =     {{The Use of AES-192 and AES-256 in Secure RTP}},
    pagetotal = 16,
    year =      2011,
    month =     jan,
    day =       12,
    abstract =  {This memo describes the use of the Advanced Encryption Standard (AES) with 192- and 256-bit keys within the Secure RTP (SRTP) protocol. It details counter mode encryption for SRTP and Secure Realtime Transport Control Protocol (SRTCP) and a new SRTP Key Derivation Function (KDF) for AES-192 and AES-256. {[}STANDARDS-TRACK{]}},
}