N4Handshakes and keep-alive

The problem

1 s on screen = 100 ms

Why is the first click on a site slower than the next one?

A new connection every time

A browser asks a server 40 ms away for something five times a second, opening a new connection for each request.

Encryption

NoneTLS 1.3TLS 1.2

Live metrics for each version of the scene
Metric	Reconnecting	Kept open	Change
target ≤ 250 ms	—	—	—
	0/s	0/s	—
	—	—	—

N4Handshakes and keep-alive

Before the first byte, TCP needs a round trip and TLS one or two more. Reusing the connection skips all of them.