2023-10-20 RFC9110, Section 16.7 First Come First Served Please see , Section 16.7 for details regarding token registrations. HTTP Hypertext Transfer Protocol any DIGIT.DIGIT (e.g., "2.0") RFC9110, Section 2.5 TLS Transport Layer Security ANY DIGIT.DIGIT (e.g., "1.2") WebSocket The Web Socket Protocol websocket The Web Socket Protocol h2c Hypertext Transfer Protocol version 2 (HTTP/2) (OBSOLETE) RFC9113, Section 3.1 connect-udp Proxying of UDP Payloads connect-ip Proxying of IP Payloads