Upgrade Mechanism

[mnot]

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).

[mnot]

Current plan:

1. HTTPS URLs

   • use NPN (or its replacement); uses OPAQUE TOKEN to negotiate
   • then send magic + SETTINGS

2. HTTP URLs
   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)

   • NO upgrade dance
   • first send magic + SETTINGS

[mnot]

Discussions seem to have converged; closing this tracking issue (although more specific issues may still be open).