%% You should probably cite rfc6050 instead of this I-D.
@techreport{drage-sipping-service-identification-05,
    number =    {draft-drage-sipping-service-identification-05},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-drage-sipping-service-identification/05/},
    author =    {Keith Drage},
    title =     {{A Session Initiation Protocol (SIP) Extension for the Identification of Services}},
    pagetotal = 19,
    year =      2010,
    month =     sep,
    day =       9,
    abstract =  {This document describes private extensions to the Session Initiation Protocol (SIP) that enable a network of trusted SIP servers to assert the service of authenticated users. The use of these extensions is only applicable inside an administrative domain with previously agreed-upon policies for generation, transport, and usage of such information. This document does NOT offer a general service identification model suitable for use between different trust domains or for use in the Internet at large. The document also defines a URN to identify both services and User Agent (UA) applications. This URN can be used within the SIP header fields defined in this document to identify services, and also within the framework defined for caller preferences and callee capabilities to identify usage of both services and applications between end UAs. This document is not an Internet Standards Track specification; it is published for informational purposes.},
}