HTTP2a

HTTP2a is a proposed extension of the HTTP/2 protocol family that has appeared in speculative writings and experimental proposals. Unlike the standardized HTTP/2, HTTP2a has not been ratified by standards bodies, and there are no official reference implementations or wide-scale deployments. It is described as an evolution aimed at addressing enduring performance and extensibility issues in HTTP/2 while preserving its core request–response semantics.

Design goals attributed to HTTP2a include more efficient multiplexing and flow control to mitigate head-of-line blocking, refined frame and stream prioritization, and an enhanced server-push model. Proposals often envision a modular transport layer with a pluggable security and transport strategy, allowing TCP-like reliability or occasional QUIC-like behavior while retaining HTTP/2-style framing. Additional ideas include improved header compression, richer observability, and extensible extension points for new features without breaking compatibility with existing HTTP/2 semantics.

Because HTTP2a is not standardized, actual implementations vary in hypothetical proposals and are not deployed in production at scale. In practice, many organizations have progressed toward HTTP/3 (which uses QUIC) and its design choices for reducing latency and head-of-line blocking, which address similar goals with a different transport model.

See also: HTTP/2, HTTP/3, QUIC, server push. References: none specified.