Fog Computing

This multi-module project is split up into 4 parts:

• sensors - To small python services producing data via a ZeroMQ PUB sockets. They can be started via docker-compose and are exposed on ports 5555 (usage topic) and 5556 (temperature topic).
• edge - a small service collecting data from 2 sensors via subscribing to a ZeroMQ PUB socket and sending over data to the cloud service via a ZeroMQ REQ socket. Data is collected every second and send over to the cloud server every 15 seconds.
• cloud - a small server waiting for messages of the edge service via a ZeroMQ REP socket which answers with aggregated sensor data.
• common for the shared code parts of the 2 other modules.

Quickstart Cloud

Copy/clone the repository to your cloud machine and just run: docker compose up cloud. On your local machine, just run docker compose up -d temperature usage edge. Make sure to set replace the first argument of the edge service command in the docker-compose.yaml with the proper address of the cloud service, for example: command: '34.32.53.149:8080 temperature:5556 usage:5555' You may want to watch an individual service's logs via docker logs -f $SERVICE_NAME.

Quickstart Local

docker compose up will start all services which will immediately start talking to each other.

How it works

The EdgeService expects the cloud service to run on localhost:8080 per default. This can be overwritten by passing an address of format host:port as first argument to the edge service.

The CloudService runs on port 8080 per default. This can be overwritten by passing a port option to the cloud service via -p or --port.

Cloud and edge service are resilient to outages of the respective other service and can be started in any order. The edge service will collect sensor data no matter if the cloud service is reachable. Usually, the edge service sends a SensorDataBatch every 15 seconds containing 15 SensorData data points. If the cloud service is not reachable, the amount of messages per batch will grow in the buffer (until no memory is left). As soon as the cloud service is reachable again, the Edge Service will send multiple batches in a row until the buffer is empty.