%% You should probably cite draft-ietf-sipcore-sip-websocket instead of this I-D.
@techreport{ibc-sipcore-sip-websocket-02,
    number =    {draft-ibc-sipcore-sip-websocket-02},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ibc-sipcore-sip-websocket/02/},
    author =    {Inaki Baz Castillo and Jose Luis Millan and Victor Pascual},
    title =     {{The WebSocket Protocol as a Transport for the Session Initiation Protocol (SIP)}},
    pagetotal = 20,
    year =      2012,
    month =     apr,
    day =       16,
    abstract =  {The WebSocket protocol enables two-way realtime communication between clients and servers. This document specifies a new WebSocket sub- protocol as a reliable transport mechanism between SIP (Session Initiation Protocol) entities and enables usage of the SIP protocol in new scenarios.},
}