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enricobuehler 0be3183cf2 docs: update README + docs site for public readiness
Refresh the README and documentation for public visitors:

- README: public-facing rewrite with accurate status for all four native
  clients (macOS, Linux, Windows, Android) and the Windows host.
- docs site: fix stale client status (Android is a full client, not a
  scaffold; Windows client is stage-1 complete + signed MSIX), add the
  missing Android client section, correct "which client" guidance.
- Windows host: corrected from "deferred/scoped" to implemented & shipping
  (NVIDIA-only, x64-only) across windows-host, roadmap, status,
  requirements, running-as-a-service, and the README.
- Remove internal infrastructure from public docs (box names, private IPs,
  SSH/token commands, deploy topology); rewrite status.md as a public
  project-status page; sanitize ci.md and implementation-plan.md.
- Update clients/android and clients/apple READMEs to current state.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-20 18:59:23 +02:00

2.9 KiB

title, description
title description
How It Works The ideas behind punktfunk — per-client virtual displays, the two protocols, and trust.

You don't need to know any of this to use punktfunk, but it helps to understand what's happening when you connect.

A virtual display, sized to your device

When a client connects, the host asks your desktop to create a new virtual display at exactly the client's resolution and refresh rate, captures that display, and streams it. The virtual display is real to your desktop — apps can be moved onto it, games open on it — but it isn't tied to any physical monitor. When the client disconnects, the virtual display goes away.

That's why a 1080p60 laptop and a 1440p120 desktop can stream from the same host at the same time, each at its own mode — they each get their own virtual display.

How the virtual display is created depends on your desktop:

Desktop How
GNOME (Mutter) A virtual monitor via the screen-cast API
KDE Plasma (KWin) A virtual output via KWin's screencast
Bazzite / Steam (gamescope) A nested gamescope session launched at the client's mode
Sway (wlroots) A headless output added to the running session

From screen to GPU to wire

Captured frames never touch the CPU on their way to the encoder. They go straight from the compositor to the GPU's NVENC hardware encoder (HEVC/H.264/AV1) and out to the network — a zero-copy GPU path that keeps latency low even at high resolutions and frame rates.

Two protocols

punktfunk speaks two protocols over the same host:

  • GameStream — the protocol Moonlight uses. Any Moonlight client connects with no special software. This is the most compatible way in.
  • punktfunk/1 (native) — a purpose-built protocol with a QUIC control channel and a UDP data channel hardened with forward error correction and encryption. It's lower-latency and more resilient on imperfect networks, and it's what the native clients (Apple, Linux, Windows, Android) use.

Both run from a single host process, so you don't choose up front — Moonlight clients use GameStream, the native clients use punktfunk/1.

Pairing and trust

The first time a device connects, you pair it: the host shows a short PIN, you type it into the client, and the two remember each other. After that the device reconnects automatically on a pinned cryptographic identity — no PIN, no account, no cloud. See Pairing & Trust.

Finding hosts

Hosts advertise themselves on your local network, so clients can discover them automatically instead of needing an IP address. The native clients and Moonlight both list hosts they find on the LAN.

Multiple devices at once

A host can stream to several clients simultaneously — your laptop and your TV both viewing (and controlling) the desktop, each at its own resolution. See Multiple devices.