Technical and regulatory changes necessary to mitigate SIPping including illegal robocalls

In this proposal, I note that the issue of illegal robocalls is an extension of a larger problem (SPIT or "SIP spam") related as much to the problems of Internet spam as telemarketing fraud, and propose a multipronged approach to mitigating SPIT including mandatory authentication of SIP messages, the establishment of a trusted registry of legitimate telemarketers and disallowing routing of calls not authenticated or in a trusted registry, and approaches borrowed from anti-UCE approaches now in testing for stopping SPIT (including Bayesian filtering and fingerprinting). I also propose several regulatory changes that provide the FTC with powerful new tools to go after the sources of SIPping, based on model laws already in place in states with aggressive DNC enforcement regulations.