HLS (HTTP Live Streaming)
HLS is Apple's segmented HTTP adaptive-streaming workflow for live and on-demand viewer delivery. For IT/firewall purposes, the important answer is that HLS has no dedicated native TCP/UDP service port of its own. Playlists, media segments, partial segments, keys, license calls, steering manifests, and related player/API calls are fetched over ordinary web infrastructure, normally HTTPS on 443, with HTTP on 80 only where the selected service intentionally uses cleartext or redirects.
Scope: HLS (HTTP Live Streaming) — select the deployed product/version; optional services require separate selection.
protocol · Catalog reviewed 2026-09-27
HLS
Related requirements
Review these entries for the services used in your design.
Infrastructure Requirements
- HTTP origin and/or CDN
- encoder or packager
- Multivariant and Media playlists
- an authored codec ladder that the target clients actually support
- segment formats such as fMP4/CMAF, MPEG-2 TS, packed audio, and WebVTT as applicable
- enough uplink/downlink bandwidth
- and, where protection is required, a working key-delivery / DRM plan. For LL-HLS, the whole path also needs partial segments, playlist delta updates, blocking playlist reload, preload hints, rendition reports, and server / cache behavior that meets Apple's low-latency configuration expectations.
Network & Physical Requirements
| Port / allocation | Transport | Connection / signal flow | Feature and requirement | Evidence |
|---|---|---|---|---|
| 80 (default) | TCP | Player → Origin / CDN | Profile requirement · Core HTTP playlists and media segments HLS over HTTP Use the playlist/segment URI and its explicit port; 80/443 are HTTP/HTTPS defaults, not HLS-exclusive listeners (RFC 9110 §§4.2.1–4.2.2). | Source checked 2026-09-27 RFC 8216, Sections 6.2.1, 6.3.1 and 8.1: server/client operation and HTTP URI example |
| 443 (default) | TCP | Player → Origin / CDN | Profile requirement · Core HTTPS playlists and media segments HLS over HTTPS Use the playlist/segment URI and its explicit port; 80/443 are HTTP/HTTPS defaults, not HLS-exclusive listeners (RFC 9110 §§4.2.1–4.2.2). | Source checked 2026-09-27 RFC 8216, Sections 6.3.1 and 8.2: HTTPS playlist and media URI |
| 443 (default) | UDP | Player → Origin / CDN | Optional · HTTP/3 HTTP/3 carriage HLS service supporting HTTP/3 | Source checked 2026-09-27 RFC 9114, Sections 3.1 and 3.2: HTTP/3 discovery and connection establishment |
Gotchas & IT Notes
- ⚠Playlist, segment, authentication, key and DRM license hosts can differ. Permit only destinations required by the service.
- ⚠Latency depends on segment/part duration, player buffering and distribution design; the protocol name is not a fixed latency promise.