Re: New Version Notification for draft-nottingham-http2-encryption-03.txt

[Paul Hoffman <[e-mail]>]

The new material on what might be called "alternate service pinning" has
the advantages and faults of any of the security pinning protocols that the
IETF makes. Please note how tortured the key pinning discussion in the
websec WG has become; there is no reason why alternate service pinning will
be any easier. This isn't to say that you shouldn't do it, just that you
should expect it to be a protracted and sometimes circular discussion full
of "but what if; so the protocol now has to".

Separately, the text in Section 4 concerns me because it seems easy to
mis-implement. That is, the API flag that says "this connection is/isn't
running under authenticated TLS" becomes critical; it is even more
important than the API flag for "this connection is/isn't running under
TLS".  Please consider calling this out more strongly in Section 4, and add
it to the Security Considerations. Encouraging developers to have a unit
test for "start a connection with unauthenticated TLS and then then try to
request an https: resource and make sure that fails".

--Paul Hoffman