EnOcean IoT Connector¶

The EnOcean IoT Connector (IoTC) allows for the easy processing of the super-optimized EnOcean radio telegrams. The IoTC is distributed as a group of Docker containers. All containers are hosted in the Docker Hub.

The IoTC is composed of the following containers:

1. enocean/iotconnector_ingress
2. enocean/iotconnector_engine
3. enocean/iotconnector_api
4. Redis
5. NGINX

Deploying the IoTC is simple using docker compose. For convenience, docker-compose.yml files are provided to easily deploy locally (i.e. with Docker) or to Azure Containers Instances (Microsoft Azure cloud account and subscription required).

The IoTC can either be deployed in:

• a public cloud (eg. Azure)
• private cloud
• on-site

IoTC containers are built for linux/arm/v7, linux/arm64 and linux/amd64

This guide will explain the basic functionality and cover the basic deployment steps and configuration options.

Documentation Version/Tag/SHA¶

0.2.2 / 2021-11-25 11:17:36+01:00 / d171914

Features¶

Ingress¶

The ingress controls all incoming traffic from ingress gateways.

• The IoTC currently supports Aruba Access Points as ingress gateways.
• Communication is executed via secure web sockets only. Secure web sockets use SSL encryption. A manual how to add a certificate to an Aruba AP is listed here.
• It detects duplicates - i.e. filter if two or more ingress gateways received the same radio signal, and makes sure each signal is processed only once.
• Processes the ESP3 Protocol. Packet Type 01 & 10 is currently supported.

Engine¶

The IoTC engine completely supports the EnOcean radio protocol standards as defined by the EnOcean Alliance. Including:

• addressing encapsulation
• chaining
• decryption & validation of secure messages
• EEP processing

Additionally the IoTC evaluates sensor health information:

• information included in signal telegram
• telegram statistics

See the Output format description for more details on what the engine can provide.

Built-in end-points¶

Available end-points are MQTT and the Azure IoT Hub. The output data format is JSON, in accordance to the key-value pairs defined by the EnOcean Alliance IP Specification.

Supported EnOcean Equipment Profiles (EEP)¶

The following EEPs are supported:

A complete description and a list of all existing EEPs can be found here: EEP Viewer.

If you are missing an EEP for your application please let us know.

API¶

The API is used to onboard EnOcean Devices into the IoTC.

The most important features are:

• most recent data and signal telegrams from a device
• get past telegrams to get past health
• telegram statistic (e.g. count, last seen) for a device and per gateway
• list of connected ingress gateways
• persistent storage of onboarded device - if volume is selected.
• Include friendlyID, location or any custom parameter for each onboarded device
• All onboarded devices can be retrieved via GET /backup or uploaded via POST /backup.
• Open API Standard 3 supporting the automatic generation of clients in several languages.
• Active flag to enable/disable telegram processing for a particular device.

The API exposes a UI interface for your convenience. Once the IoTC connector has been deployed, the full API specification is available via the UI web Interface.

NGINX¶

NGINX is used as a proxy to protect the interface of the IoTC. The user is required to provide a certificate for usage.

A Dockerfile / azure.dockerfile and corresponding dependencies (start.sh and nginx.conf ) are provided at /deploy/nginx/ in case the proxy needs to be rebuilt or customized.

redis¶

Redis is used as a message broker & cache for communication between different containers.

The API¶

The API is OpenAPI compliant, supporting the automatic generation of clients in several languages. The full API Specification is available here or via the web Interface, once the IoTC has been deployed.

If you specified a volume storage at deployment then all changes done in the API will be persistent even after containers are restarted or updated.

Web UI of management API¶

1. Opening the API url on a browser will display the API reference. The URL is https://<hostname of the container group or IP address>:443. Example: https://192.167.1.1:443 or https://myiotc.eastus.azurecontainer.io:443

2. If you used a self-signed certificate and did not add it to your browser you will see a warning, please continue according to your web browser.

3. Login using the BASIC_AUTH_USERNAME & BASIC_AUTH_PASSWORD you specified in environmental variables.

4. The API complies with Open API Standard 3.

   1. Download the API Specification as JSON

      

   2. Go to the editor e.g. online here and generate your client code.

      

5. You can use the Try it out function to execute any of the available commands.

   

Telegram statistics - sensor & gateway statistics¶

The API provides telegram statistics of the individual devices and per ingress gateway.

[
    {
    "device": {
      "hardwareDescriptor": "AP-305",
      "mac": "d01546c204a2",
      "softwareVersion": "8.7.1.1-8.7.1.1"
    },
    "stats": {
      "lastSeen": "1619210924",
      "notProcessed": 0,
      "succesfullyProcessed": 78662,
      "totalTelegramCount": 78662
    }
  },
  {
    "device": {
      "hardwareDescriptor": "AP-305",
      "mac": "24f27f551bf4",
      "softwareVersion": "8.7.1.0-8.7.1.0"
    },
    "stats": {
      "lastSeen": "1619210928",
      "notProcessed": 0,
      "succesfullyProcessed": 91526,
      "totalTelegramCount": 91526
    }
  }
]

[
  {
    "device": {
      "activeFlag": "true",
      "customTag": "",
      "destinationEurid": "ffffffff",
      "eep": "a5-09-09",
      "friendlyID": "co2_Hardware2",
      "isPTM": "false",
      "location": "Hardware 2",
      "sourceEurid": "051b03c9"
    },
    "stats": {
      "lastSeen": "1619210854",
      "notProcessed": 0,
      "succesfullyProcessed": 1057,
      "totalTelegramCount": 1057
    }
  }
]

The stats section is defined as:

TelegramStatistics:
      properties:
        lastSeen:
          description: Timestamp of last valid telegram from device in UTC seconds.
          type: string
        notProcessed:
          description: Count of not processed telegrams due to various reasons & NOT forwarded on egress.
          type: integer
        succesfullyProcessed:
          description: Count of succesfully processed telegrams & forwarded on egress.
          type: integer
        totalTelegramCount:
          description: Total count of received telegrams.
          type: integer

End-points¶

Available end-points are MQTT or Azure IoT Hub.

Output Format¶

The data is included in a JSON file as key-value pairs following the EnOcean Alliance IP Specification. Example JSON outputs from selected devices are available below.

{
    "sensor": {
        "friendlyId": "Multisensor 1",
        "id": "04138bb4",
        "location": "Cloud center"
    },
    "telemetry": {
        "data": [{
            "key": "temperature",
            "value": 23.9,
            "unit": "°C"
        }, {
            "key": "humidity",
            "value": 29.0,
            "unit": "%"
        }, {
            "key": "illumination",
            "value": 67.0,
            "unit": "lx"
        }, {
            "key": "accelerationStatus",
            "value": "heartbeat",
            "meaning": "Heartbeat"
        }, {
            "key": "accelerationX",
            "value": -0.13,
            "unit": "g"
        }, {
            "key": "accelerationY",
            "value": 0.08,
            "unit": "g"
        }, {
            "key": "accelerationZ",
            "value": -0.97,
            "unit": "g"
        }, {
            "key": "contact",
            "value": "open",
            "meaning": "Window opened"
        }],
        "signal": [],
        "meta": {
            "security": [],
            "sensorHealth": [],
            "stats": [{
                "egressTime": "1611927479.169171"
            }]
        }
    },
    "raw": {
        "data": "d29fce800863b502a620",
        "sender": "04138bb4",
        "status": "80",
        "subTelNum": 0,
        "destination": "ffffffff",
        "rssi": 77,
        "securityLevel": 0,
        "timestamp": "1611927479.166352"
    }
}

{
    "sensor": {
        "friendlyId": "co2_Hardware2",
        "id": "051b03c9",
        "location": "Hardware 2"
    },
    "telemetry": {
        "data": [{
            "key": "co2",
            "value": 627.45,
            "unit": "ppm"
        }, {
            "key": "learn",
            "value": "notPressed",
            "meaning": "Data telegram"
        }, {
            "key": "powerFailureDetected",
            "value": "False",
            "meaning": "Power failure not detected"
        }],
        "signal": [],
        "meta": {
            "security": [],
            "sensorHealth": [],
            "stats": [{
                "egressTime": "1611927535.0731573"
            }]
        }
    },
    "raw": {
        "data": "a500005008",
        "sender": "051b03c9",
        "status": "01",
        "subTelNum": 0,
        "destination": "ffffffff",
        "rssi": 80,
        "securityLevel": 0,
        "timestamp": "1611927535.0714777"
    }
}

{
    "sensor": {
        "friendlyId": "switch1",
        "id": "feee14ab",
        "location": "Entrance"
    },
    "telemetry": {
        "data": [
            [{
                "key": "energybow",
                "value": "released",
                "meaning": "Energy Bow released"
            }]
        ],
        "signal": [],
        "meta": {
            "security": [],
            "sensorHealth": [],
            "stats": [{
                "egressTime": "1611927462.4711452"
            }]
        }
    },
    "raw": {
        "data": "f600",
        "sender": "feee14ab",
        "status": "20",
        "subTelNum": 0,
        "destination": "ffffffff",
        "rssi": 71,
        "securityLevel": 0,
        "timestamp": "1611927462.469978"
    }
}

Each output JSON consist of three sections:

• sensor - stored information about the sensor provided at onboarding via the API
• telemetry - information interpreted by the engine
  • data - sensor data included in the message and encoded via the EEP
  • signal -raw sensor health data included in the message and encoded as signal telegram
  • meta - meta information about the message added by the engine
• raw - raw message information
• rssi - radio signal strength information. Important to track radio quality

Sensor Health Information¶

Selected devices from EnOcean transmitt additonally to their data messages also messages about their internal states or events. This messages are refered to as signal telegrams. Signal telegrams include information about the:

• percentage of remaining energy available in the energy storage
• how much energy is provided via the energy harvester
• availability and status of a back up energy store
• for additional information see the signal telegrams specification and data sheet of your EnOcean product

The rssi radio signal strength information provides important information about connectivity. We recommend to track it and raise and alarm if the level drops or changes significantly.

General operation can be checked by the lastSeen parameter provided by the API. Some devices have a periodic communication pattern. Checking deviations / fluctuations in the pattern can help to detect issues before quickly.

Sensor Meta Events¶

The IoT Connector provides on the MQTT egress interface important information about events that were detected in regard to the sensor status, data transmission or behavior. The topic structure is /sensor/<id>/meta/event. The JSON Schema of these events can be found in the download section.

There are these types of events:

• Security Events

  • MAC_VALIDATION_ERROR - a received message could not be authentificated with the included CMAC. This could be an indication for a security attack.
  • RLC_REPLAY - a received message has a lower message sequence counter then the previous. This could e an indication for an replay attack.
  • DEVICE_SEND_NOW_UNSECURE - a device which was onboarded as secure is now transmitting as non secure. This is an indication of compromision the set security level, possible attack.

• Health Events

  • FIRST_TIME_SEND - an onboarded device transmitted for the first time.

• Processing / Transcoding Events

  • EEP_DECODE_ERROR - the receive message could not be decoded with the specified EEP. This is an indication for an corrupted radio message (if occuring on limited basis) or wrong specified EEP (if occuring pernament).
  • EEP_NOT_FOUND_ERROR - the specified EEP of an device is not know to the IoTC. Please contact support in such case.

Gateway Health Events¶

Selected AP (e.g. Aruba AP) transmitt meta infromation about their internal states refered as Gateway Health Updates. This infromation is forwarded on the MQTT interface. The topic structure is /gateway/<mac>/health. The content is similar to the console log messages. The JSON Schema of these events can be found in the download section.

The purpose of this message includes these two use cases: - Still-alive message from the gateway. Know the gateway is operation. - EnOcean USB Dongle information of the gateway. Know the USB Dongle is correctly operationg.

Technical Requirements¶

The different containers of the IoTC require the Docker environment to run. Specific requirements (i.e. RAM, CPU) depend on the number of connected end points to the IoTC at runtime and their communication frequency. Typical installations (e.g. 100 connected AP, 500 EnOcean end points) can be run at common embedded platforms on the market e.g. RPi gen 4.

The IoTC was load tested in laboratory conditions with 200 Gateways / APs with trasnfering in total 2000 EnOcean Messages within 10 seconds. No issues or message lose was detected.

For Azure Cloud deployments we recommend to use the docker-compose.yml file listed in azure_deployment directory.

Used 3rd party components and libraries, OSS Components¶

Components:

• Redis Community(https://redis.io/)

• Python 3.8 (https://www.python.org/)

• Docker Community (https://docs.docker.com/get-docker/)

• NGINX Community (https://www.nginx.com/)

• Mosquitto (https://mosquitto.org/)

Python Libraries:

• Async Redis (aioredis,https://github.com/aio-libs/aioredis-py, MIT License)

• HIREDIS (hiredis,https://github.com/redis/hiredis,BSD License)

• Licensing (licensing,https://github.com/Cryptolens/cryptolens-python,MIT License)

• Protobuf (protobuf,https://developers.google.com/protocol-buffers/,https://github.com/protocolbuffers/protobuf/blob/master/LICENSE)

• Pydantic (pydantic,https://github.com/samuelcolvin/pydantic/,MIT License)

• Redis (redis,https://github.com/andymccurdy/redis-py,MIT License)

• Tornado (tornado,https://github.com/tornadoweb/tornado,Apache License 2.0)

• Flask (flask,https://flask.palletsprojects.com/en/1.1.x/,BSD=https://flask.palletsprojects.com/en/0.12.x/license/)

• Conexion (conexion,https://github.com/zalando/connexion,https://github.com/zalando/connexion/blob/master/LICENSE.txt)

• Azure (azure,https://github.com/Azure/azure-sdk-for-python,MIT)

• Bitstring (bitstring,https://github.com/scott-griffiths/bitstring,MIT)

• crc8 (crc8,https://github.com/niccokunzmann/crc8,MIT)

• paho-mqtt (paho-mqtt,http://www.eclipse.org/paho/,BSD=https://projects.eclipse.org/projects/iot.paho)

• pycryptodome (pycryptodome,https://github.com/Legrandin/pycryptodome,https://github.com/Legrandin/pycryptodome/blob/master/LICENSE.rst)

• pyinstaller (pyinstaller,https://github.com/pyinstaller/pyinstaller,https://github.com/pyinstaller/pyinstaller/blob/develop/COPYING.txt)

License Agreement and Data Privacy¶

Please see the License agreement here.

Please see the Data privacy agreement here.

Disclaimer¶

The information provided in this document describes typical features of the EnOcean software products and should not be misunderstood as specified operating characteristics. No liability is assumed for errors and / or omissions. We reserve the right to make changes without prior notice.