Are html5 streamed videos cacheable?

Question

I'm using jwplayer to play videos in html5 mode. Videos are in mp4 format.

What I'm seeing in the network tab are bunch of network requests with 206 status (partial download). So my understanding is -> video is just being streamed in partial chunks, 1-2 Mb each.

But can those chunks be cached in the browser? Currently I'm seeing video just being re-streamed every time...

Answer 1

With reference to this answer: Yes, 206 responses are cacheable. This is also explicitly stated in RFC 7233, section 4.1:

A 206 response is cacheable by default; i.e., unless otherwise indicated by explicit cache controls

This does not mean that browser do cache those, of course. But they certainly can.