3 ms·

HTTP/3 is built with TLS 1.3 and have faster handshake. Second - HTTP/3 define some "idle" state of connections like 30 seconds or even more. So you can downlo

HTTP/3 is built with TLS 1.3 and have faster handshake. Second - HTTP/3 define some "idle" state of connections like 30 seconds or even more. So you can download something and then nothing. Here HTTP 0.9/1.0/1.1 and /2 closes connections. On HTTP/3 it was set to idle - nor closed. And let say after 15 sec you need new resource. On HTTP/3 connection flow continue where was stopped. On previous versions you must make TLS handshake and then to make new request. This mean performance penalty because congestion control will start with values similar to 0.

Matthias247 6y ago
This is pretty much unrelated to the discussion earlier on (which was about the interaction of different flow control mechansisms). But nevertheless one answer that tries to clear up some misunderstandings: You can reuse connections with every HTTP version up from HTTP/1.1. The main difference between HTTP/1.1 and HTTP/2 and /3 is that you can't make concurrent requests on a single connection with HTTP/1.1, but you can with /2 and /3. For how long a connection will stay open after a request will be determined by keepalive settings on the client and server side. All HTTP versions up from 1.1 allow you not to use a connection for 30s and then make another request.