@techreport{tschofenig-sipping-framework-spit-reduction-04,
    number =    {draft-tschofenig-sipping-framework-spit-reduction-04},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-tschofenig-sipping-framework-spit-reduction/04/},
    author =    {Hannes Tschofenig and Henning Schulzrinne and Dan Wing and Jonathan Rosenberg and David Schwartz},
    title =     {{A Framework to tackle Spam and Unwanted Communication for Internet Telephony}},
    pagetotal = 24,
    year =      2008,
    month =     jul,
    day =       14,
    abstract =  {Spam, defined as sending unsolicited messages to someone in bulk, is likely to become a problem on SIP open-wide deployed networks. A number of solutions have been proposed for dealing with Spam for Internet Telephony (SPIT) and unwanted communication, such as content filtering, black lists, white lists, consent-based communication, reputation systems, address obfuscation, limited use addresses, turing tests, computational puzzles, payments at risk, circles of trust, and many others. This document describes the big picture that illustrates how the different building blocks fit together and can be deployed incrementally.},
}