The Engineering Behind PhotonFile

• Simpler, predictable connections. WebRTC requires extensive NAT traversal logic, ICE negotiation, and multiple connection candidates. Relays give a single, predictable, stable path every time.
• No peer IP exposure. WebRTC exposes each client's network addresses to the other party. With PhotonFile's relay model, neither side ever learns the other's IP.
• Controlled performance. TURN servers (the fallback for many WebRTC flows) were never designed for multi-gigabyte, high-throughput file streams. PhotonFile relays are tuned specifically for sustained large transfers.
• Better privacy guarantees. With WebRTC, metadata such as ICE candidates, fingerprints, and DTLS handshakes are shared peer-to-peer. A relay keeps all signaling server-side and avoids passing identity-like network data to the recipient.
• Easier encryption story. PhotonFile's model layers TLS + optional client-side AES-GCM cleanly. WebRTC enforces DTLS-SRTP under the hood, adding complexity and limiting control over the exact flow of encrypted file data.
• Works everywhere without permission prompts. Many corporate networks, firewalls, and mobile carriers block or throttle WebRTC. HTTPS + WSS through a relay works reliably across essentially every environment.

Relays give a consistent, private, high-throughput path purpose-built for file transfer, not generic real-time communication. That matches the goals of Ephemeral File Transfer: simple, reliable delivery with a tight privacy envelope.

• A random symmetric key is generated per transfer using the browser's Web Crypto API.
• File data is encrypted in streaming chunks (AES-GCM) on the client, and the relays only ever see opaque ciphertext.
• The decryption key is kept in the link fragment (#...), so it is not sent in HTTP requests or written to server logs.
• Anyone you share the full link with can decrypt the file in their browser; without the key material, relay traffic is not useful on its own.

This model is designed so that even if a relay is inspected after the fact, there are no retained keys and no plaintext files to recover, only short-lived encrypted traffic that was handled ephemerally by default.

PhotonFile is designed from the ground up to forget by default. The system is built around live relay and short-lived state, with privacy-oriented defaults rather than long retention windows.

Minimize surface area. Minimize lifetime. Maximize privacy.

• Relays handle transfer data in memory, keeping state short-lived and clearing it when the session ends.
• There are no server-side keys. With client-side encryption enabled, keys never leave the browser and never enter relay traffic or logs.
• State is deliberately ephemeral. Relays do not maintain upload histories, access logs tied to transfers, or any form of retrievable session data.
• Decryption happens entirely in the browser. Because the key never leaves your browser, the relay only sees opaque ciphertext and cannot decrypt or recover anything.

This Ephemeral File Transfer architecture is designed so that after a session ends, the system has little to remember: no retained keys, no plaintext files, and no long-lived transfer state tied to your session.