HTTP/2 and HTTP/3
HTTP/2 introduces streams: multiplexed, ordered sequences of frames sharing one connection. We show how a slow response no longer blocks the connection, then shift to HTTP/3, where streams move down into the transport itself, so a lost packet no longer blocks a stream.
Topics covered:
- HTTP/1.1's connection limits and why browsers open six of them
- HTTP/2 streams, frames, and the single shared connection
- Head-of-line blocking inside TCP: why one loss stalls all streams
- HTTP/3 on QUIC: streams in the transport, loss isolation
- 0-RTT resumption and what it costs in replay risk
- Deployment reality: h2 everywhere, h3 where CDNs reach
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