This is a tracking ticket for issues related to the mechanism for upgrading from HTTP/1.x.
As per our charter, this is:
A negotiation mechanism that is capable of not only choosing between HTTP/1.x and HTTP/2.x, but also for bindings of HTTP URLs to other transports (for example).
a. existing connection / new connection without context
- Upgrade Dance; uses OPAQUE TOKEN to negotiate
- then send magic + SETTINGS
b. new connection with context (e.g., because you used DNS hint, header hint, prior knowledge)
Clarifying upgrade options (#1).
Discussions seem to have converged; closing this tracking issue (although more specific issues may still be open).