@misc{rfc8433,
    series =    {Request for Comments},
    number =    8433,
    howpublished =  {RFC 8433},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC8433},
    url =       {https://www.rfc-editor.org/info/rfc8433},
    author =    {Dale R. Worley},
    title =     {{A Simpler Method for Resolving Alert-Info URNs}},
    pagetotal = 45,
    year =      2018,
    month =     aug,
    abstract =  {The "alert" namespace of Uniform Resource Names (URNs) can be used in the Alert-Info header field of Session Initiation Protocol (SIP) requests and responses to inform a voice over IP (VoIP) telephone (user agent) of the characteristics of the call that the user agent has originated or terminated. The user agent must resolve the URNs into a signal; that is, it must select the best available signal to present to its user to indicate the characteristics of the call. RFC 7462 describes a non-normative algorithm for signal selection. This document describes a more efficient alternative algorithm: a user agent's designer can, based on the user agent's signals and their meanings, construct a finite state machine (FSM) to process the URNs to select a signal in a way that obeys the restrictions given in the definition of the "alert" URN namespace.},
}