Transport Profiles (Prism)¶

Quill uses Prism transport profiles for adaptive protocol selection.

Profiles¶

Profile	Protocol	Best For
Classic	HTTP/1.1 + H2	Enterprise proxies, legacy networks
Turbo	HTTP/2 end-to-end	Internal cluster traffic
Hyper	HTTP/3 over QUIC	Browser/mobile, lossy networks

Negotiation¶

Client sends preference:

Prefer: prism=hyper,turbo,classic

Server responds:

Selected-Prism: turbo

Configuration¶

use quill_client::QuillClient;
use quill_core::PrismProfile;

let client = QuillClient::builder()
    .base_url("http://api.example.com")
    .prefer_profiles(&[
        PrismProfile::Hyper,
        PrismProfile::Turbo,
        PrismProfile::Classic,
    ])
    .build()?;

Profile Comparison¶

Feature	Classic	Turbo	Hyper
Protocol	HTTP/1.1	HTTP/2	HTTP/3
Multiplexing	No	Yes	Yes
Head-of-line blocking	Yes	Partial	No
Connection migration	No	No	Yes
0-RTT	No	No	Yes
Proxy compatibility	Best	Good	Limited

Deployment Patterns¶

Edge H3 → Interior H2¶

Browser ──[HTTP/3]──► Edge ──[HTTP/2]──► Services
         Hyper            Turbo

H2 Everywhere¶

Client ──[HTTP/2]──► LB ──[HTTP/2]──► Services
        Turbo             Turbo