Posts Tagged ‘IoT’
[Devoxx FR 2021] IoT Open Source at Home
At Devoxx France 2021, François Mockers, an IoT enthusiast, delivered a 32-minute talk titled IoT open source à la maison (YouTube). This session shared his decade-long journey managing over 300 open-source IoT devices at home, likening home automation to production IT challenges. From connected light bulbs to zoned heating and sunlight-responsive shutters, Mockers explored protocols (ZigBee, Z-Wave, 433MHz, Wi-Fi) and tools (Home Assistant, ESPHome, Node-RED, Ansible, InfluxDB, Grafana). Aligned with Devoxx’s IoT and cloud themes, the talk offered practical insights for developers building cost-effective, secure home automation systems.
IoT: A Growing Home Ecosystem
Mockers began by highlighting the ubiquity of IoT devices, asking the audience how many owned connected devices (00:00:30–00:00:45). Most had over five, some over 50, and Mockers himself managed ~300, from Philips Hue bulbs to custom-built sensors (00:00:45–00:01:00). He started with commercial devices a decade ago but shifted to DIY solutions five years ago for cost savings and flexibility (00:00:15–00:00:30). His setup mirrors production environments, with “unhappy users” (family), legacy systems, and protocol sprawl, making it a relatable challenge for developers.
IoT Protocols: A Diverse Landscape
Mockers provided a technical overview of IoT protocols, each with unique strengths and challenges (00:01:00–00:08:15):
- ZigBee: Used by Philips Hue and IKEA, ZigBee supports lights, switches, plugs, motion sensors, and shutters in a mesh network for extended range. Devices like battery-powered switches consume minimal power, while plugged-in bulbs act as repeaters. Security issues, like a past Philips Hue hack allowing remote on/off control, highlight risks (00:01:15–00:02:15).
- Z-Wave: Similar to ZigBee but less common, used by Fibaro and Aeotec. It supports up to 232 devices (vs. ZigBee’s 65,000) with similar mesh functionality (00:02:15–00:02:45).
- 433.92 MHz: A frequency band hosting protocols like Oregon Scientific (sensors), Somfy (shutters), and Chacon/DIO (switches). These are cheap (~€10 vs. €50 for ZigBee/Z-Wave) but insecure, allowing neighbors’ devices to be controlled with a powerful transceiver. Car keys and security boxes also use this band, complicating urban use (00:02:45–00:04:00).
- Wi-Fi: Popular for startups like Netatmo (weather, security), LIFX (bulbs), and Tuya (garden devices). Wi-Fi devices are plug-and-play but power-hungry and reliant on external cloud APIs, posing risks if internet or vendor services fail. Security is a concern, as hacked Wi-Fi devices fueled major botnets (00:04:15–00:06:00).
- Bluetooth: Used for lights, speakers, and beacons, Bluetooth offers localization but requires phone proximity, limiting automation (00:06:00–00:06:30).
- Powerline (CPL) and Fil Pilote: Protocols like X10 and fil pilote (for electric radiators) use electrical wiring but depend on home wiring quality. Infrared signals control AV equipment and air conditioners but require line-of-sight and lack status feedback (00:06:45–00:08:00).
- LoRaWAN/Sigfox: Long-range protocols for smart cities, not home use (00:08:00–00:08:15).
Open-Source Tools for Home Automation
Mockers detailed his open-source toolchain, emphasizing flexibility and integration (00:08:15–00:20:45):
Home Assistant
Home Assistant, with 1,853 integrations, is Mockers’ central hub, supporting Alexa, Google Assistant, and Siri. It offers mobile apps, automation, and dashboards but becomes unwieldy with many devices. Mockers disabled its database and UI, using it solely for device discovery (00:08:30–00:09:45). It integrates with OpenHAB (2,526 integrations) and Domoticz (500 integrations) for broader device support.
ESPHome
ESPHome deploys ESP8266/ESP32 chips for custom sensors, connecting via Wi-Fi or Bluetooth. Mockers builds temperature, humidity, and light sensors for ~€10 (vs. €50 commercial equivalents). Configuration via YAML files integrates sensors directly into Home Assistant (00:10:00–00:11:45). Example:
esphome:
name: sensor_t1_mini
platform: ESP8266
api:
services:
- service: update
then:
- logger.log: "Updating firmware"
output:
- platform: gpio
pin: GPIO4
id: led
sensor:
- platform: bme280
temperature:
name: "Temperature"
pressure:
name: "Pressure"
humidity:
name: "Humidity"
Node-RED
Node-RED, with 3,485 integrations, handles automation via low-code event-driven flows. Mockers routes all Home Assistant events to Node-RED, creating rules like bridging 433MHz remotes to ZigBee bulbs. Its responsive dashboard outperforms Home Assistant’s (00:12:00–00:14:00).
InfluxDB and Grafana
InfluxDB stores time-series data from devices, replacing Home Assistant’s PostgreSQL. Mockers experimented with machine learning for anomaly detection and room occupancy prediction, though the latter was unpopular with his family (00:14:15–00:15:15). Grafana visualizes historical data, like weekly temperature trends, with polished dashboards (00:15:15–00:15:45).
Telegraf
Telegraf runs scripts for devices lacking Home Assistant integration, sending data to InfluxDB. It also monitors network and CPU usage .
Ansible and Pi-hole
Ansible automates Docker container deployment on Raspberry Pis, with roles for each service and a web page listing services . Pi-hole, a DNS-based ad blocker, caches queries and logs IoT device DNS requests, exposing suspicious activity.
Security and Deployment
Security is critical with IoT’s attack surface. Mockers recommends:
- A separate Wi-Fi network for IoT devices to isolate them from PCs .
- Limiting internet access for devices supporting local mode .
- A VPN for remote access, avoiding open ports .
- Factory-resetting devices before disposal to erase Wi-Fi credentials .
Deployment uses Docker containers on Raspberry Pis, managed by Ansible. Mockers avoids Kubernetes due to Raspberry Pi constraints, opting for custom scripts. Hardware includes Raspberry Pis, 433MHz transceivers, and Wemos ESP8266 boards with shields for sensors (00:19:45–00:20:45).
Audience Interaction and Lessons
Mockers engaged the audience with questions (00:00:30) and a Q&A , addressing:
- Usability for family (transparent for his wife, usable by his six-year-old)
- Home Assistant backups via Ansible and hourly NAS snapshots
- Insecure 433MHz devices (cheap but risky)
- Air conditioning control via infrared and fil pilote for radiators
- A universal remote consolidating five protocols, reducing complexity
- A humorous “divorce threat” from a beeping device, emphasizing user experience
Conclusion
Mockers’ talk showcased IoT as an accessible, developer-friendly domain using open-source tools. His setup, blending ZigBee, Wi-Fi, and DIY sensors with Home Assistant, Node-RED, and Grafana, offers a scalable, cost-effective model. Security and automation align with Devoxx’s cloud and IoT focus, inspiring developers to experiment safely. The key takeaway: quality data and user experience are critical for home automation success.