Do we already have strong security protections for our Internet services? For many years now, we have had numerous cryptographically enhanced protocols. Standards and suites like S/MIME, Transport Layer Security (TLS), IP Security (IPSec), OpenPGP, and many others have been mature for years, have offered us a range of protections and have been implemented by a wealth of code. Indeed, based on these protections, we already count on having “secure” eCommerce transactions, secure point-to-point phone calls that our neighbors can’t listen in on, secure Virtual Private Networks (VPN) that let us remotely connect to our internal enterprise networks, etc.  However, our Internet security protocols have all excluded a very important step from their security analyses; none of them describe a crucial step called secure key learning.  That is, before we can encrypt data or verify signatures, how does someone bootstrap and learn what cryptographic keys are needed?  In lieu of a way to do this, we have traditionally prefaced the security protections from these protocols with techniques like Out of Band (OOB) key learning (learning keys in an unspecified way) or Trust on First Use (ToFU) key learning (just accepting whatever keys are found first), and each protocol must do this separately (and potentially in its own, different, way).  This is because the protocols we use for protections have not formally specified a standardized way to securely bootstrap protocols.

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