# VTech VM901: reconstructing camera authentication and media access

> VTech VM901 reconstructs the camera's authentication and media workflow for a Home Assistant bridge. The Go and C implementation uses TUTK/Kalay transport, performs the documented X25519 and ChaCha20-Poly1305 exchange, decrypts H.264 and G.711 media, and publishes streams through go2rtc.

- Type: Case study
- Targets: Protocol
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-06
- Added to the catalog: 2026-11-08
- Original resource: <https://github.com/Termina1/vtech-vm901-home-assistant>
- Primary source: <https://github.com/Termina1/vtech-vm901-home-assistant/blob/383375e757a3664844c864b394cd465ecb08d21f/README.md>
- Catalog page: <https://awesomerea.org/resources/vtech-vm901-home-assistant-case/>
- Record JSON: <https://awesomerea.org/resources/vtech-vm901-home-assistant-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/vtech-vm901-home-assistant-case/index.md)

## Requirements & limits

- **Prerequisites:** An owned or authorized VM901 camera and account are required.
- **Prerequisites:** The Android/bionic ARM64 runtime needs locally extracted SDK libraries and application values; the account bootstrap uses an authenticated request from the official app.
- **Testing evidence:** The author reports testing on a local camera during the original research.
- **License:** MIT License for repository source; locally extracted components retain their own terms.

## Primary sources

1. <https://github.com/Termina1/vtech-vm901-home-assistant/blob/383375e757a3664844c864b394cd465ecb08d21f/README.md>
2. <https://github.com/Termina1/vtech-vm901-home-assistant/blob/383375e757a3664844c864b394cd465ecb08d21f/docs/architecture.md>
3. <https://github.com/Termina1/vtech-vm901-home-assistant/blob/383375e757a3664844c864b394cd465ecb08d21f/NOTICE.md>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.